I think that Disney needs to compete head-to-head with Universal. I've never been there and honestly don't care to ever go. Ever since they had a billboard on I-4 proclaiming that they "Pay More Than The Other" I've lost a lot of respect for them and don't want to give the money.
Here's my idea:
Create a Villains Theme Park! Make it primarily "thrill" rides with that distinct Disney touch. It would also give teens their own "park" so to speak. Of course, I know that they have to keep it family and child-friendly, but this is Disney and they're the best of doing this.
Here's just one of the rides I thought of:
A racing/dueling roller coaster with one track white and the other black for Cruella de Ville.
I really think that creating more Everest-type rides will be in Disney's best interest. Like I said, it'll keep more people on property and give pre-teens, teens and young adults a theme park dedicated primarily to them!