I would mash together a lot of suggestions from BSN and here into a non-horde mode epic final sequence that I feel would be a lot more satisfying.
Firstly, I'm not going to go into great detail on this. Specifics such as who are available as suicide squad things, or how successful they are in each role has been explained elsewhere, and I don't feel like typing it all out. In addition, I won't write specific lines of Dialogue either.
Basically:
Suicide Mission mechanics for the attack on Earth. Shepard is allowed input on which fleets go where, as he assembled them, he knows their strengths better than anyone, but can opt to leave it for someone else to choose. You pick three fleets for Sword, Three for Shield and three for Hammer. The fleets are made up of the fleets you gathered throughout the game, and each can only be assigned to one group. Their success is based off how strong they are, which is based off how well suited they are to the role given, and how strong they are out of how strong they could have been.
Hammer is then merged with the infantry forces, such as Jack and her Biotics, and then split into 4 groups: 3 Hades canon groups, and 1 Reaper IFF Conduit group.
The three Hades canon groups have to be strong warriors, and will push through to destroy three of the 4 Hades canons, whilst Shepard goes after the other one.
The Reaper Conduit IFF group should be strong, and good with Tech. They must decrypt a Reaper IFF required to use the London Conduit to access the Citadel.
Each group and team's success - Sword, Shield and the Hammer squads - will result in different things happening throughout the ending.
Sword fleet jumps in. Starts off like it does in ME3, only its the fleets you chose for Sword jumping in and engaging the Reapers. This applies for below details as well, only who is in sword is included in these.
The battle could start like it did, as I love that wall of firepower. But then, it splits into showing you your choices, and some of the things you collected, in action.
The Destiny Ascension engages a Reaper Capital Ship, and blasts through it, killing it outright. It is then swarmed by Reaper Destroyers. If you have the Geth, they move to intercept and save the Ascension. The Alliance and Turians work together to bring down another Reaper, and the Volus Dreadnought Kwunu does a run straight through Reaper lines, firing all of its Thanix guns [Thanix guns are its main gun, its broadside canons, and every weapon it has. Walls of Thanix would literally be peeling away from the Kwunu in all directions], if the Kwunu was acquired, dealing large amounts of damage to the Reaper fleets. The Salarian fleet is under fire from several Reapers, and even with their Thanix guns their line is failing. If there, the Krogan fly in and ram several Reapers, killing them. The Quarian flotilla is engaging Reapers in a failing battle. An admiral aboard a ship turns to his crew and says "For the Homeworld. Kela'sa-" and is cut of as his ship rams a Reaper, taking it down and damaging nearby Reapers with the explosion.
Hammer then lands, and the squads push out towards their objectives. You see each of the Hammer fleets flying into Earth's atmosphere, and some of their troops getting out, before Shepard is dropped down too and sent towards his Hades canon. Once the Hades canon is taken down, the results of the other squads is shown. Note: If Sword fleet fails, then one or more squad missions may end with the death of the squad, or the failure of that mission.
He see's each of the Hades groups run towards the canons, set up the heavy weapons and open fire. If successful, the Hades canon explodes, and the squads retreat back to the FOB with minimal resistance. If semi-successful, they destroy the canons but are cut off from the FOB and killed by Reaper forces. If unsuccessful, due to Sword failing AND a semi-successful squad - A reaper destroyer lands in the way of their shot and absorbs it, before turning and firing on the squad, wiping them out.
We then see the IFF team holding off Reaper forces whilst one of them works on decoding the IFF. If successful, the squad holds out and cracks the IFF, before being extracted by a shuttle. If semi-successful, they hold out with heavy casualties and send off the decrypted IFF before jumping in the Shuttle. The shuttle is shot down during their escape. If unsuccessful - requires Sword fleet failure and semi-successful squad - a Reaper destroyer lands next to the squad's location and obliterates them.
Shepard then pushes forward to the Conduit. He and numerous others push through the conduit into the Citadel. If the IFF was successful or semi successful, they all make it inside - bar some casualties to marauder shields - and begin fighting their way to Citadel control. If IFF team unsuccessful, most die, and Shepard alone makes it into the Citadel alive - saved by the pile of corpses left behind by the others trying to make it through, who ended up killed by unsafe transit - maybe flung at high speeds into a wall or something.
Shepard then begins to fight his way through the Citadel. As this happens, the Shield fleets and the Crucible jump in.
Shepard then fights through the Citadel, section by section. In the Refugee docking bay, Conrad Verner and Jenna [If both alive] are barricaded with a bunch of other refugees down the end of the docking bay, Conrad in his N7 armour. They are fighting against an encroaching army of Reaper forces. If the IFF was successful or semi successful, the group that Shepard bought up with his helps to remove the Reaper threat, then decides they'll hold ground there and help the refugees. Shepard says a few words to Verner and Jenna, then moves on...
In the commons Shepard finds C-Sec, Barla Von, Char's wife, General Oraka and an assortment of others fighting off Reaper forces as they approach. If Shepard acquired the Cerberus Turret Schematics, come turrets have been set up to hold off the Reapers, which saves the lives of some of the Civilians as the Reapers attack. If Shepard hadn't given permission to search through private files to C-Sec, they were unable to apprehend Cerberus operatives in the civilian group, one of whom shoots Oraka in the back as he tries to defend them. If the militia was allowed, some of the Civilians are armed, and protect their unarmed brethren whilst fighting. If Shepard secured Oraka the black market weapons, C-Sec uses them to their advantage and take out a Brute quickly before he charges the barricade and kills numerous civilians. After the Reaper waves are finally over, Shepard says a few words to Oraka and the others he knows, then moves on...
Shield fleet approaches the battle at Earth, and begins aiding Sword fleet. Any cutscenes not shown previously will be shown now [Note: There are success or failure cutscenes for each fleet in the space battle as well, dependent on whether they themselves are successful. All that is required for a group success is for 2 of the three fleets to be successful].
Shepard enters Huerta Memorial. Holed up at the end are Jacob, his wife, Dr Michelle, the PTSD soldier and those two civilians who you could convince to volunteer to do medical help or W/E [Each if alive and appropriate to be there]. Shepard fights off a preliminary wave, then an additional one comes in. Their opening volley kills one of the group - unless you completed Kasumi's mission, in which case Jondum Bau and his Spectre Compatriots blast through the Windows and swing into the hospital, devastating the Reaper forces. Shepard says a few words to the group, then moves on...
At Purgatory, Aria is involved in a fight against the Reapers. Several of the bar's patrons are holed up at the end of the bar. If Shepard upgraded the power grid for the club, Aria is able to do something similar to Liara in LOTSB, and cause an outflow of electricity from the club's equipment to annihilate the Reapers. If not, she is shot.
If she is shot, and Shepard recovered the Banner of the Ninth Regiment or W/E, a group of Turians from the first fleet, on leave and drinking at the time of the attack, look to each other, one raises the banner and the others rise up and defend Aria with cover fire. If the Reapers return fire. If Shepard recovered the texts on the ways of the Asari Huntress, the Asari general or W/E has used them to help train her fellow Asari, and the group erects a barrier protecting the Turians, who proceed to wipe out the Reaper forces.
If the Banner was never recovered, the Turians never rise, and the Asari defend Aria instead before being shot and killed. If the book on the ways of the huntress was never recovered, the Asari don't defend the Turians/Aria, and they die.
Shepard fights off the next wave with the group, says a few words to Aria, then moves on...
Shield Fleet nears the Citadel, and moves into defensive positions to protect the Conduit, waiting for Shepard to open the arms as the two colossal objects slowly float towards each other.
Shepard arrives in the Embassies. Officer Noles and Balak [Or whoever substitutes him if he's dead] are holding off the Reapers near the Spectre office. If Balak's quest was completed, he sees Shepard and knows the end of the war is near. Several diplomats bunkered with him and Noles are injured and hurt, as are some of his Batarian compatriots. He turns to his fellow Batarians and tells them 'For our people', then charges forward into the Reaper horde, determined to save his fellows, and provide Shepard a safe path ahead to end the war, and stop the Reapers. If the pillars of strength were Recovered, the Batarians with Balak have them, look towards them, then rise up and join Balak in the charge, devastating the Reapers and saving Balak with few casualties. If not, Balak dies in his charge, but manages to stop the Reapers none the less. Shepard helps hold off another wave of attacks, then says a few words to Noles and Balak before moving on...
Down on Earth, the squad mates you left behind are fighting. If alive:
-Grunt, Wrex and Aralak company are behind a barricade on the ground. Another squad begins taking fire from a horde of ravagers. They look at each other, then rise up and charge the Ravagers, Wrex crying out how they'll never take the Krogan's future from them.
-Tali, Kal'Reeger [Retcon him being killed on Twitter] and the Quarains are taking fire at their position. They look at each other and Reeger prepares to rise with his men. If the Geth Primes were acquired, a geth ship flies down, chased by a swarm of Reaper Occuli, and performs an orbital drop of the Primes, who charge the Reaper forces attacking 'The creators', saving the Quarians. If the primes were not acquired, Reeger and his men take a last stand against the Reapers, stopping them, but at the cost of their lives. Tali and the other Quarians fall back to a more defensible position.
-Liara and Javik are fighting alongside Asari commandos, taking down a wave of Reaper attacks. Suddenly, the scream of Banshees can be heard, and close to a dozen of them start jumping towards the group. If Samara was saved, she and the Justicars charge in and execute the Banshees, saving the group. If not, Javik looks to Liara, then faces the Banshees and summons all his Biotic energy, unleashing the fury of a dead race against them, and charging them whilst the commandos cover him. He dies in a blaze of glory, the last voice of the Prothean's extinguished whilst protecting others from the Reapers.
-Garrus and Victus are holed up in one of the Turian's portable buildings, taking heavy fire from a group of Marauders. Garrus looks to Victus, and both rise - rifles out - to confront their fate. If Zaeed was saved, he charges in with a small group of Mercs and catches the Reapers of guard, taking them down. If not, Garrus and Victus snipe out the enemy unit, but take heavy fire. Both fall down, and lay bleeding on the ground, still shooting at Reapers attacking other groups down the ramp of the building.
I think you get the picture, so I'll leave it there.
Shepard arrives in the Citadel tower, and charges forward. He fights his way through groups of Reapers, and makes it to the council chambers - where the council are, being protected by C-Sec. The Turian councillor is armed and fighting back, whilst the Salarian councillor provides Tech support, and the Asari raises barriers to protect the group. If human councillors, they do nothing and the C-Sec forces fall. Shepard makes his way to the Citadel control panel seen in ME1, and tells the Council to fall back to the Embassies. They do so, and Shepard opens the arms of the Citadel.
The Crucible continues to float towards the Citadel, and it begins to deploy as it does so, eventually latching on to the Citadel. Suddenly, an alert comes from Shield, Harbinger is headed to the Citadel. He charges through a Shield dreadnought, and through the arms as they slowly open. He places himself infront of the Citadel tower, and has his final confrontation with Shepard. Maintaining the Dark and mysterious nature of the Reapers, Harbinger tried to intimidate Shepard. Shepard has a brief talk with Harbinger, who reveals nothing. After the talk finished, Harbinger begins to charge his beams. Now Shield is required.
If Shield is successful [2 successful fleets if all Hades towers destroyed, 3 successful fleets if 1 Hades canon survived, impossible to achieve success if 2 or 3 Hades canons survived], Harbinger is hit with heavy fire from Shield fleet, that tears through his shields and cuts through him. Harbinger tells Shepard that this is not over, before exploding and dying. Shepard then chooses to activate the Crucible, or if the risk of major collateral damage is too great.
If Shield is not successful, Shepard is given a 1 second Interrupt to run forward and activate the Crucible before he is shot by Harbinger and killed.
If Shield is not successful, but the Normandy was fully upgraded in ME2, and was given the new piping for the engine in ME3, The Normandy charges through, fires its Thanix gun into Harbinger, then Joker sacrifices himself, Ramming straight into Harbinger, destroying them both. Shepard then chooses to activate the Crucible, or if the risk of major collateral damage is too great.
If Shepard activated the Crucible, lines of power run down the Citadel as all of its energy is diverted to firing the Crucible. If the Collector base was saved/destroyed [Whichever provided the most war assets], then it handles the strain fine. If the opposite, the Citadel experiences large amounts of damage after firing, and begins to break apart. The Citadel spreads its arms, the emits a burst of energy that flies out from it. As the energy hits each ship, it reacts with the Eezo in the cores. A large enough concentration of Eeze - like in the Reaper cores - and it reacts violently, discharging all the energy being channelled through the eezo, dropping all Reaper systems. This energy wave hits the Relays. It is transmitted down each relay before the Relay is shut off and turned dormant - like the Charon relay was before we unEarthed it and activated it. The quantum shielding employed by the Relays causes the energy discharge from the eezo to magnify the signal, rather than damage the Relays themselves, and project it across the Mass Relay network. Every Reaper in the galaxy experiences a complete system shutdown, and begin to fall prey to dangers such as gas giants, planetary gravity, other ships engaging them. The fleets above Earth decimate the Reaper forces, before re-activating the Charon relay and returning to their home systems to finish off the Reapers there. Shepard is regarded as a hero.
If Shepard did not activate the Crucible, Sword, Hammer and Shield Victories are taken into account.
Things taken into account:
-Was Sword Fleet 1 Successful
-Was Sword Fleet 2 Successful
-Was Sword Fleet 3 Successful
-Was Shield Fleet 1 Successful
-Was Shield Fleet 2 Successful
-Was Shield Fleet 3 Successful
-Did Hades team 1 survive
-Did Hades team 2 survive
-Did Hades team 3 survive
-Did the IFF Team survive
If:
-1 or 2 Yes's: The forces at Earth are decimated. No survivors. The Reapers go on to harvest this cycle, and the cycles continue
-3 or 4 Yes's: The forces at Earth are defeated. The Normandy escapes, and Liara deploys her secret onto many garden worlds around the galaxy. The Reapers harvest this cycle, but the next cycle find Liara's message, and begins preparing for the Reapers.
-5 or 6 Yes's: The battle for Earth is successful, but the fleets suffer heavy losses. After each falling back to defend their homeworld, the galaxy falls to the Reapers. Liara's message is left on many garden worlds around the galaxy. The next cycle finds her message, and begins preparing. Due to heavy casualties to the Reapers, an extra cutscene is shown with the next cycle's fleets gathered around the Citadel. The Citadel opens, and the Relay to Darkspace activates. Reapers begin pouring through, but come under instant fire from the fleets the second they leave the Relay.
-7 or 8 Yes's: The battle for Earth is a success. Whilst suffering heavy casualties, the fleets move off to defend the rest of the galaxy. Palaven and Thessia are written off as completely lost, and all council races suffer significant casualties. 20 years later, the galaxy is declared free of Reaper influence, and goes on to live happily and begin rebuilding. Numerous squadmates and friends die during the war. Earth has suffered major damage from the fight however, and is left uninhabitable.
-9 Yes's: The battle for Earth is a major success. The fleets suffered moderate losses, but removed the Reaper presence from Earth. They move on to battle for the rest of the galaxy, and save defeat the Reapers where they find them. Palaven and Thessia are badly damaged, whilst Earth is relatively ok. This causes resentment towards humanity, who many believe used the fleets to save their own planet at the cost of others. The Council races do not suffer particularly significant casualties - at least no more so than any other race - however, and everyone begins rebuilding.
-10 Yes's: The battle for Earth is remembered as possibly the greatest success in galactic history. All forces performed at their peak, and devastated Reaper forces with minimum casualties. The battle was short, and after saving Earth the fleets quickly returned to the worlds of Palaven and Thessia to carry out operations there, which are also major successes. Earth, Palaven and Thessia are saved and remain inhabitable. The galaxy's forces suffer heavy losses ridding the galaxy of Reapers, however they manage it and the galaxy enters its first age of complete peace and prosperity. Rather than Shepard be hailed as a hero, the men and women of all the militaries are, which sparks a rise in the number of new recruits to peacekeeping forces.
An epilogue would be included, showing the results of each of your choices, what happened to your squadmates and other major figures and groups, what happened to Shepard and what happened on each of the main worlds.
