First, I'd like Jazz's sprite completely redone. Maybe not to his original form but for crying out loud, give the sprite some PERSONALITY! A FACIAL expression at least! Oh well, at least he looks good in the cutscenes.

Second, although the Saurians and Chameleons (weren't there chameleons in JJ1? Giant generic green lizard, anyway.) were good for variety, (besides turtles, what did JJ2 have? Lab rats, dogs, bats, ravens....yawn. Seen it all before) I'd like to see more turtles besides Stormtroopers, like all the varieties in JJ1. (Doofusguards and Schwarzenguards>>>>>>Stormtroopers)

Thirdly, give Jazz his run back. 'Nuff said.

Fourth, I'd like better levels. The levels in JJA were somewhat repetitive: find switch and/or key, kill enemy, open door, repeat. Also, except for the robot level (whose name escapes me), the levels were fairly generic: futuristic city, seen it. Ice level, seen it. (Granted, JJ2 had an ice level, but JJ2 is the only game whose ice level I've seen as Hell frozen over. That was honestly a creative idea) Castle level, seen it. I miss the quirky environments of JJ1: Fanolint, Orbitus, Letni, etc. I'd also like non-linear levels like the old games.

Last, more bosses. JJA only had what, five? Six? I liked how some bosses had to be beaten in ways besides "reduce life meter to zero", though.