Kingdom Hearts 4: 15 Disney Worlds We Need To See
8. The Simpsons
Similarly to Futurama, The Simpsons would add a nice layer of cynicism to Kingdom Hearts.
The Kingdom Hearts series has always been so earnest which I would never want it to stray too far from as that earnestness is what makes Kingdom Hearts, Kingdom Hearts, but just one level where everybody doesn't enable Sora's love of hearts, friendship, and the light would be pretty funny.
Exploring Springfield with the Simpsons to find some random MacGuffin would be a great excuse to visit the numerous iconic locations from the show whilst fighting off a bunch of comically themed Heartless. Finish the level off with a boss fight against Kang and Kodos and we're in business.
Of course, with a show like The Simpsons, fighting is rarely present so it could also serve as the replacement for the Hundred Acre Woods. The world could be filled with mini-games that involve helping out numerous characters from the show.
As long as we get a fully explorable Springfield all will be good with the world.