Pinball mainly. The game is just pure fun and both Pinballs were the only way I could even think about "catching them all". They're fun games, and I don't see why they shouldn't make a return.
In the same vein as that, the puzzle games. Not like Trozei, but the first two puzzle games. I found those a lot more fun than Trozei, and like to see them updated for the new generations.
I would say Colo. and XD, but there's not a lot left to do in the storyline except for "After another time skip, Cipher rises again!" But maybe something like it but different in a way, though Orre would be fun to continue learning about.
