I want to battle the Queen of Hearts I never understood why you dont, all of the other world fights are with disney characters well except monstro and traverse town and destiny'island. I think the strongest boss you have to battle will be Riku (if you battle him) or one of the other Org memebers maybe even DiZ. As for optional... I want a brand new boss Seprioth can die for all i Care. I want someone like Kurt Zisa. Brand new character.