Too many boss battles, not enough scenes, the character himself was fine imo. His scenes in Aqua's scenario were terrible except for the Venitas one where he came off like a psychopath wanting another keyblade war.
The scenarios in general just didn't leave good room for original KH character scenes, too much development juice went into the minigames and the multiplayer compatibility. I would rather have it on the PS2 for the extra story scenes and the extra space to be used more beneficially than multiplayer functionality in a game that allows for a non-ending stream of invincibility frames achieved by spamming dodge roll.