I have to respectfully disagree with you @Swing on your first comment and on Brave and on the contrary, I feel it's going to be Pixar films that more suited for level design/environment to explore in as a world, so besides Toy Story & Monster's Inc. the other Pixar films that look likely to become a worlds in a future KH game are: The Incredibles, Brave, Coco, Inside Out, Onward and the upcoming film, Soul.Not many Pixar movies can translate well into a KH world. Besides Monster, Inc., and Toy Story the only one that comes to my mind would be The Incredibles. A Bugs Life would also work really well, but sadly it is one of Pixar's weaker movies and is not profitable for Disney in any way. Brave would also work, but the reception for that movie was kinda... meh. Not awful, not good, just really in the middle, a 5/10-movie.
I also don't think we would be seeing television properties in the KH series or anything from Marvel and Star Wars.