either set it in a remake of London, u r all saying real names of places this wont work as it would b bad publicity for the place and if u look u have
Liberty City - NY
Vice City - erm...Miami
San Andreas - Detroit
Things GTA 4 missed are;
Aeroplanes
Go-Karts
Military Base
Gym (i loved the San Andreas weight control)
Wider variety of clothes
a mansion (boat parking space)
Surfing mini-game
multi-player minigames like pool etc
story mode online co-op
Dildo as a weapon (lol i'm not a perv just thought it was hilarious in the last 1)
impound yard (when ur infernus disappears u know where its gone)
more melee weapons (where did the sword go)
missions set with more people (like say u do missions for Triads, Yakuza, Russian Mafia, Rastas, Brittish (i mean like the guy from vice city ...paul?)
Car customization
never ending assassin missions

Card gambling game - texas hold-em
better radio i loved Maurice Chavez so funny but Lazlo just didnt do it.
fighting cyndicate (along with different fighting styles yet another san andreas exclusive)
my want list is long i'm sorry but gta lacked in the extra's which san andreas had
oh yeah i want cars to run out of petrol
a big red button (like the heart in the statue but u shoot it and every building blows up)
use more weapons if ur a passenger a drive-by with an AK would b wkd
own a gang - u choose what they wear the cars they drive.
a car show room u can choose to buy or rob the cars. if the police see u in a stolen car they chase u and u can bribe them for the small offenses like speeding
burglary missions another from san andreas.
and finally protection rackets and owning local businesses like vice city u could get a regular income from the malibu club
The missions & characters i enjoy and would like to see again
Niko without the depression of the war as mentioned in an above post
Dwayne - dwayne my favourite character so keep him as he is
Little Jacob - erm mayb
Another bank robbery, car races and assassin missions, ambulance, fire truck,
better fist fights a redesign (i'm being picky now ive just been playing the bourne conspiracy and the fighting is amazing.) an escape from prison mission would be good halfway through the game niko gets caught ends up in jail a couple of missions in jail like drug dealin, beatin someone up for protection money, a trading system so u can acquire the tools u need 4 the escape.
and another 1 for laughs a gun closet in each safe house that has a bundled in mini-game of cleaning ur weapons and taking them apart and putting them together. then again i like guns so it could just b me. o yh a safety catch on each gun. only jokin.
finally carry a limited amount of weapons i mean shoving an RPG down ur trouser leg...pffft or if u carry too many weapons police see bulges and get suspicious ... never mind.
police do random stop n searches of people.
so closing it the game is far from perfect. it is a good game with excellent graphics. but the police AI and the cabaret club didnt do it 4 me. so if developers read this u have got some work 2 do chop chop i want GTA V by xmas