The reason why Universal is taking in such a huge chunk of Disney's draw recently is obviously Harry Potter.
It's a HUGE scale project. On top of it being so freaking huge and the series being so popular both books and movies.. It's not just one attraction. It's an entire land.
The problem Disney's having is that none of their movies/series that are being used are as popular as Harry Potter.. With the exception of Star Wars.. But they have yet to do anything with Star Wars. As much as I hate Star Wars, I also hate Harry Potter.. They need to create a full-out land themed to Harry Potter at HS.
On top of that, Avatarland is just gonna flop I believe. It'll be popular when it first opens, but there really isn't any fan base or popularity from it to be as great as Harry.
Disney needs to invest in things just as popular as Harry Potter.. That's what is financially successful as a business. Say what you will, but a Frozen-themed land would probably be almost as popular as Harry Potter land. Sorry that you don't like the idea, but it's true.
So Disney has these to choose from if they don't want to invest in outside resources that AREN'T owned by Disney... Frozen, Star Wars, PIXAR (not the toy story playland, but an actual pixar-themed land with full scale attractions, shops and restaurants), MARVEL themed land (with what they can work with.. BH6, Guardians..)..
That's all I can think of that would live up to Harry Potter's popularity. Going outside of Disney, Doctor Who in EPCOT's World Showcase would probably bring in a large amount of Who fans. They already lost the Nintendo idea so that's out.
All I'm saying is Disney isn't going to gain back any percentage lost to Harry Potter with only single attractions and meet and greets. They need a full-scale land based on one of the most popular genres of all time.. And Star Wars should be the way to start. At least, I'd prefer that over Frozen.