Well, I don't care about any of the poll options, but coming up with an answer was surprisingly difficult. A lot of the games that immediately came to mind either don't have a sequel to begin with, like Wizard With a Gun, or they've already had a third entry, like Final Fantasy: Crystal Chronicles. A gut answer is Mega Man ZX, but this is probably just recency bias. I played through all of the Mega Man X, Zero, and ZX games recently, and ZX was definitely my favorite series from a gameplay standpoint. They were Metroidvanias, with the gimmick being that you had the power to transform. In the first game, you could only transform into 5 different humanoid forms (plus one secret one), but then in ZXA you could transform into all 5 of those forms again, and you could transform into bosses as well, which could get pretty wild. It would be interesting to see what they'd do with the series now. I doubt that's what I'd want the most, but I'm at work, so I can't exactly go looking through all my games atm! :p Edit: Gravity Rush 3, no question. How in the world I forgot about this is beyond me.