If we could find an open source PS2 Emu to work from, we could eliminate L2 and R2 because they aren't used in the game.
r1 (where he flies into air) - select
l3 - l
r3 - r
analog stick L - d pad
analog stick r - the triangle, square, circle, x keys
Sure, it's never going to happen, but it'd be awesome if it did.
If we could get a PS2 emu down, rather than having to figure out how to program an analog nub R, R3, L3, R2, and L2, we could just map the keys I showed above, and Katamari Damacy would work fine.
That'd be awesome.