I want Brave in any form in KH! If we don't get a world I would expect at least Merida to make an appearance as a summon. I mean she could blast away heartless with superior archery skills and make a finishing move with Sora and her riding Angus and destroying Heartless with shots and tackles at full speed.
Second place would be 101 dalmatians. Shadow Swarm? Pls! We have Dalmatian Swarm :v