Parts of MSHI, WWoHP and Suess are all I care for in IoA. I can be in and out (and have been many times) in a matter of a few hours, leaving fully satisfied and getting everything done that I enjoy.
The park desperately needs a nighttime show and help over in Toon Lagoon. The JP expansion should definitely help and if we are getting a Lorax ride, that will extend the day as well. Just because Potter is in the park doesn't mean i'm willing to spend a full day there. WWoHP and The High in the Sky Seuss Trolley are pretty much the ONLY additions to the park since it opened 14 years ago. It's a good park, but it still needs a lot of love. IMO, more than USF at this point.