Just watch me, after openjazz is finished. I can spriting, and JJ1 sprites haven't got too much frame, and they not even too big, so I can handle them in the future, if somebody will make the code changes for them. If needed, I'll show you works, I've been done before.

About adding spaz new moves... It can be only ballanced, if jazz would have some new moves too, but I've got an idea, how to ballence it, without tottaly change the jj1 gameplay:
Jazz: He should have that uppercut, but he could only jump high as his running jump, he couldn't be controlled while he falled back to his starting position. So you couldn't cheat with using this move, to jump higher.
Spaz: The "buttstomp" or how is it called. That would be his new way, to beat enemyes. Maybe he shouldn't use this move against bosses, to prevent cheat (defeating them too easily), and bosses should hurt him, while doing this move.
Lori: Spinning kick. But it should be shorter, than Lori's basic jump.

And all of these should be just as a special mod, not basically added. This mod would be a lot of fun, I think