Oh the things that could be done
Overall
A 5th park might be nice, but not the elite park the rumours talk about. Not a must though unless there's a truly exceptional idea behind it. A focus on expansion of the existing parks would fill the same void and still sell more passes as people took more time in the existing parks.
Expansion of the Monorail lines would be cool as well although not likely.
Magic Kingdom
The expansion/redo of Fantasyland is a great idea in general. The Seven Dwarves mine coaster would be a great addition. Replacing the Ariel meet and greet with a Little Mermaid dark ride is an equally good idea. Convert Snow White into either a Beauty and the Beast or Fairies dark ride. Poohs Playful Spot could be converted into an enchanted neverland forest accomatading meet and greet for Fairies with a small enchanted lagood area for the previous Ariel meet and greet. Give Tom Sawyer island a buff and shine to more accomadate the playground need.
Tommorrowland could also use a new attraction to fill the spaces left open by the demolishing of the Galaxy theatre and the slow decline of Stitch`s Supersonic celebration. Perhaps somethign themed around Wall-E. And the speedway needs a revamp, I don`t care if they decide to make it cars themed or not but at least replace the vehicles with electric carts.
Epcot
The re-do of the imagination pavillion is a must. It doesn`t have to be the original but somethign in the same spirit woudl be fine. Bring back the pairing of Dreamfinder and Figment and will the pavillion with colour and wonder again instead of blackness with an occasional senses event. Ensure that the activities in the play area actually work (No one I know has ever been able to get any of the morphing photos to work for them). Update Honey I Shrunk the Audience into something a little more timely.
Ellen`s Energy Adventure could also use an overhaul. Once agian the ride is feeling dated (those same dinosaurs have been around since the park opened it seems) and a new take on this important message is sorely needed. Perhaps somethign a little more interactive could be put here.
Wonders of Life needs to re-open as well and fill that gaping hole. Cranium Command was an excellent attraction that coudl be easily updated. Body Wars was fun enough for it`s time but somethign new woudl need to go there. A large part of the rest of the area should probobly go toward nutritional education in this day and age where obesity is becoming more of a factor in young lives.
World Showcase could use a new country (My favorite candidates are Russia, Greece, Spain and Austrailia) with a new attraction as well. Also no fewer than two attractions should be added ot the existing countries (my favorite runours were the Canadian log flume ride, the German or Japanese Matterhorn and the boat ride through Venice for Italy).
Hollywood Studios
Continue the rumoured expansion of
Pixar Place with the Monsters Inc coaster, the re-theming of the Honey I Shrunk the Kids playground, the new Cars attraction from DCA (If it`s any good) and hopefully more great ideas.
Continue the update of Star Tours.
Add the Indiana Jones ride from California.
Find another viable teen/adult movie franchise that can be expanded on in this park. This may require shelling out bucks for rights (and hence will probobly never happen) but would be the best bet for Disney to at least somewhat combat Harry Potter at Universal.
Move the hat from in front of the Chinese theater. It`s a nice hat and I have no problems with it I just think it`s misplaced.
Animal Kingdom
Actually the attractions that Animal kingdom has are all very good. The key here is major expansion. I`d love to see some form of Beastly Kingdomme come to life. Perhaps even re-name the land Mythic Kingdom so as to not only include things like dragons but you could also throw in some Disney properties so far not represented like Hercules. This plus a few new attractions in areas like Africa, Asia or even Camp Minnie-Mickey would quickly turn this from a half day park to a two day park.
Downtown
The shops and restaurants are fine, Disneyquest might need a facelift. Also they need to bring back some nightlife to this area. Even re-opening the Adventurers club and creating one or two new clubs would do the job, seperate covers for the clubs instead of admission to the area would be fine.
Resorts
Finish Pop Cen
Start creating a few new resorts (when things start turnign around) that are not outsourced. The fact that so many people can spend days in disney just hotel hopping and checking out the different resorts is a definate money maker for them. It gives people a relaxing day with somethign interesting to do without going off property so spend their meal money elsewhere.