Not one of the New 3dses with the stronger processing power? Xenoblade Chronicles should be avoided. It's just not compatible.
Well, doing a lot of stand by to stand by, I've amassed a lot of games I like, and some have already been mentioned. You might wanna invest in a 126 gig card upgrade. I've gone pretty heavy on the digital.
Scribblenauts Unmasked Puzzle Solving using words to summon objects, and/or people. It has a fairly solid database of DC comic characters.
Senran Kagura Burst It's actually 2 games in the Senran Kagura series as a bundle. It revolves around a LOT of fan service, some surprisingly good writing, and some solid brawler controls. You can only play as female characters.
Senran kagura Deep Crimson (If you get it physical, shoot for the DD version. The sound track is worth it, imo.) The Sequel to Burst, it improves on the brawling, adds some giant monster bosses, and lets you play as a guy via DLC or data from burst. Again, pretty solid writing, immense fanservice, and solid gameplay.
Lego Batman 3 If you've played a lego game, you've played this, more or less. Melee enemies with a watered down Arkham combat system, have access to dozens upon dozens of assorted DC characters, find hidden stuff.
Style savvy Trendsetters It's a fashion game where you run your own store! Beneath all that it's a pretty solid puzzle game, management game, and there's a lot of character customization, though you can only play as a girl.
Tomodachi Life It's a somewhat interactive fish bowl where the fish are actually little avatars that do zany things!
Fantasy Life A pretty great RPG.
Shantae and the Pirate's Curse A solid platformer, great writing, nice character design. The series has something of a cult following for a reason.
Retro City rampage It's like a top down saints row minus the heavy character customization, though you can get codes to change your appearance.
Smash Bros It's a solid fighting game with a massive roster, simple controls, an added dungeon mode of sorts where you run through a maze and try and get as much powerups as possible to prepare for the final battle with the rest of the dungeon crawlers.
there's amiibo support allowing you to train your own AI fighter.
Street Fighter IV Not a whole lot to say. It's Street fighter IV but with some 3d options, and the ability to assign 4 buttons on the touch pad.
Fire emblem Awakening A solid tactical RPG.
Fire emblem Birthright, Conquest, and Revelations these improve on the formula.Birthright, and Revelations have a more free battle system, while Conquest takes up a more traditional approach to fire emblem where you don't get much freedom in mission choices rather it focuses on fighting through a plot.
All 3 are parts of a whole.
there's limited amiibo support for Roy, Marth, Robin, and Lucina (*Shakes fist angrily at the heavens for making a Lucina Amiibo so hard to find in a physical location.*)
Pokemon Battle World In this you control a wind up toy version of a pokemon, and scoot around an area fighting, and capturing other pokemon. Unlock stuff, there's a simple plot.
Pokemon battle Trozei It's pokemon through a match 3 style game. There's gimmicks to some pokemon, and gimmicks to some battles.
Pokemon Picross I can't super recommend this, but it's free. You use numbers to decode where dots go to make something of a picture.
Pokemon Shuffle A free version of Pokemon trozei, but not quite as robust.
As for a main game pokemon, waiting for Sun and Moon might be optional, if not X/Y and/or OR/AS are all good.
Pokemon bank. For 5 dollars a year you have access to an online service that lets you move pokemon from OR/AS, and X, and Y. Likely Sun and Moon as well.
Project Xzone gets a little tedious due to the pacing of the battles, but seeing the chaos on screen as multiple game characters from Darkstalkers to Xenoblade, street fighter to tekken just combo the crap out of targets is pretty neat, imo.
Project Xzone 2 does ok in fixing the pacing problem.
Rune Factory 4 Create a character, help grow a farm, fight monsters, improve equipment, and skills in a real time top down RPG.
Mighty Switch Force is a game where you solve mazes to arrest criminals by alternating blocks to be in the foreground, or the background.
Radar mission It's a cheap, gameboy emulated Battle Ship game with variants on the rules.
Samurai Warriors Chronicles 3 Third person brawler that puts you in the shoes of a character you create and then experience the battles that helped unite Japan.
Hyrule warriors legends A third person brawler that puts you in the shoes of assorted Legend of Zelda characters including impa, Zelda, gannon, Toon Link, Linkle (A girl that dresses like link, and believes she's the chosen hero thanks to an artifact in her family. She mauls enemies hard with her dual auto-crossbows... and she has an army of Cuckoos), Fi, Marin, Sheik, Tetra, Volga, Wizzro, Darunia, Medli, King daphnes, and some characters created for this game in specific such as Lana a sorceress of light, and Cia who is a sorceress of darkness. I still haven't unlocked all the characters.
There's a neat adventure mode.
Lots to do.
Also it has Amiibo support. It mostly unlocks rewards like weapons, rupees, and materials that help in making your warriors stronger.
Basically any Zelda game.
Puzzle Quest Challenge of the warlords. A match 3 RPG where you blend quests on an overworld map with the aforementioned match 3 with some strategy behind it as each battle is a duel and what colors you match matter.
Terraria It's like a 2d minecraft with more direction. the maps are smaller compared to Console, and PC versions, but it's serviceable.
OlliOlli A side scrolling skateboard game that charges you with doing assorted tricks.
Nintendo badge arcade A more fair crane game simulator with some occasional free plays that lets you win themes to decorate your 3ds, and badges that you can likewise decorate with by placing them in icon sockets, or on folders. It's free to play and fairly entertaining. you can buy extra plays if that's your thing. It requires internet connectivity.
Kersploosh You help guide assorted objects around obstacles down a well to the bottom.
Final fantasy Explorers is a little rough but still nice. It's a 3d brawler at a casual pace. Kill stuff, get better equipment, wash, rinse repeat. there's online multiplayer that works well.
Starship Defense is a variation of tower defense where you place assorted turrets on "star ships" which kinda gets to be a stretch as thins go on to fend off assorted smaller starships.
Zombie incident is a platformer. I hadn't gotten too deep into it honestly, but the price point is low.
Demon King Box A cheap quasi-moba where you create an army of monsters, and/or robots, summon them on a lane, and try to get them to the end so they can beat up the boss on the other side.
Adventure Bar Story You play as a girl looking to open a restaurant which also involves going out and fighting monsters for ingredients.
Monster Hunter Generations releases today. Finally, one can play as a Palico, aka a Nyanta. Kind of a big deal to long time fans. You create a hunter, go out into one of 4 villages, fight monsters, scavenge their corpses, build better equipment to go out again.
Some of these monsters include frikking ginormous wyverns, a T-Rex sorta monster, furry giant wolves, giant horned rabbits that can wreck your shit, a woolly mammoth, an so forth. It takes tactics, and talent. It's one of the few games where you do not level up your stats, rather rely on better equipment (Or, heck, you can go out with no armor what so ever if you're confident) to be more efficient at killing.
There's over a dozen weapon classes to pick from, and multiple fighting styles of each. Huge swords, massive guns, bows, hammers, horns, lances, and so forth.
And you get to play as cats!
And online Multiplayer!
Rusty's Real Deal baseball A game revolving around a sad old dog guy that loves baseball and sells videogames revolving around baseball. The first minigame is free! You can haggle on the price of the rest.
Mini Mario and friends Amiibo challenge. Got any Amiibo? May as well get this for free. Guide windup toys across a map. the toys have various abilities depending on the amiibo used.
Side Vs Pocket is an old gameboy game that can be downloaded. It's a pool game with some tournament stuff.
There's a vast array of Megaman games now.
Of course there's a massive amount of DS games at your disposal, and generally really cheap, too, like Final fantasy tactics Advance 2, Civilization, etc. There's more than a few lists of some of the greatest DS games out there.
I'm exhausted (Not from making this list, I was exhausted before I started). that's about all I can think of. I really hope that if you do get a nintendo handheld it brings you lots of joy!
