Nice. I think that the largest flaw is quite simply, uneven park guest distribution. Magic Kingdom has about as many rides and attractions as all the others do combined and thus, Magic Kingdom is the 3rd largest of the 4 but has nearly twice as many visitors as any other park. I think the other parks need to play catch-up and open some new attractions. Lots of them.
Cut off. Since the automation was added, it screwed up the spiel. The spiel will play too early, too late, and sometimes not even at all. Also, the monorail will play a different line's audio. (ex: resort playing express)
Epcot: Need to do something with the old Wonders of Life, Universe of Energy, and Odyssey restaurant areas. They also need more countries in the World Showcase. Why not turn the Odyssey and that odd little "tribal" area between Germany & China in to India and Brazil ? Those two countries are sorely missing IMHO.
Hollywood Studio: feels like half a park right now what with the construction towards the back and the closure of the Great Movie Ride. But I assume the completion of the construction project will alleviate this.