I wouldn't want for them to make many TV-licensed games on 3DS, to be honest, just because it would probably be limited to a few more family-friendly shows and of course, the 3DS has it's own limitations, but hey, anything is better than nothing (*looks at the Last Airbender movie and then deletes his account*).
Another Gravity Falls game would be nice, plus another Regular Show game - both could be 2D because it's probably easier to get right with a platformer, but if Regular Show could have a 3D game, I'd basically make it a really weird clone of The Simpsons: Hit & Run.
I'd also like a 3D Sword Art Online RPG-action game where it's just set in Aincrad and instead of the really bad story after like episode 5, they could re-do the story of Kirito making his way to beating the big bad (trying to avoid spoilers) without literally every girl he meets falling in love with him! xD
Kind of beating a dead horse here, but a game based on The Flash could be really good. Like, maybe a 2D speedrunner game or even a 3D one but that's most likely going to be very hard to pull off with the 3DS' hardware. The Flash is quite a fun, kid-friendly show IMO and well, I'm sure it would sell well with the TV show also doing some of the best numbers (in terms of ratings) out of all of the current superhero TV shows.
Also, I quite like The Rolling Girls so I'd like if they could do something with that
.