Mentioning this but I think atleast in the terms of how Disney is right now, and how they are cooperating with NBCUniversal as it is on the sake of Marvel Superhero Island with what is there; that they have an understanding and a example of showing where Universal pushes more and more what can be done with the licensing agreements there.
I think at the very least for Hollywood--on a pure fundamental technical level; that it makes more sense to keep The Simpsons as long as you can. It isn't harming either group to have The Simpsons on Universal property, it promotes the brand and merchandise continues to sell seemingly quite well. Plus for USH, Springfield USA is used yearly for The Simpsons Wrap Parties (and we've been even seeing specialty food items being made for those wrap parties). Raises the question on what you do with The Simpsons Ride, but I think there is sense to keep The Simpsons at UOR and USH.