Is Sinbad disney?? If he is he'd be the most kick-ass.
Only the chibi Sinbad at Tokyo Disneysea's Sinbad ride is Disney: http://www.tdrfan.com/tds/arabian_coast/sinbad/
I'd choose the Spring Sprite from Fantasia 2000, Figment, Madame Leota, and Walt Disney riding the Carolwood Pacific.
The Sprite could constantly heal your HP while she'd use plant growth to impale enemies.
Figment could come down on the Dreammobile and his combo move with Sora would absorb all Heartless in the area.
Madame Leota could float around using her haunted musical instruments with a combo move similar to the Stitch one.
Walt Disney would come riding the Carolwood Pacific(the miniature train from his backyard) and Sora would just hang on as the train just barreled into enemies.