What IOA needs before becoming a park that takes more than a day to fill everything:
-Return of Island Skipper Tours (maybe just a tour around the lagoon? could be round-trip) - not likely though, submarines could be cool RV I think some sort of attraction for the lagoon is needed, not the old Skipper Tour but something there would help big time.
-Dr. Doom replaced with a ToT-esque experience (still based on Fantastic Four) Honestly, Doom is pretty damn well themed for a basic amusement ride, don't see the need for this.
-Overhaul for Toon Lagoon This is a given, something will be done there by the end of the decade for sure.
-New E-ticket on Thunder Falls (Kong fulfills this) This is going to be huge for IoA
-Jurassic World overlay for JP (enhancements to River Adventure, flat ride in CJ, replaces Pteranodon Flyers with a more high-capacity attraction) I don't get the whole Jurassic World overlay thing. Jurassic Park is a well known brand and is more recognizable for people. Maybe some minor things from the movie, but an entire overlay is too much IMO. It does need some sort of 2nd attraction and a RA refurb though.
-D-ticket family coaster in TE plot This seems likely to happen, but Universal appears to want to fry their bigger fish first
Jurassic World aquarium and Mr.DNA dark ride to replace current Discovery Center An aquarium sure, but the dark ride won't happen
Great Hall added to Hogwarts I don't see this happening
DC removed for HP 3.0 (Forbidden Forest with Big Thunder-style Hippogriff family coaster, Ford Anglia flat ride/Fantasyland-style dark ride, and Shrieking Shack show/walk-through) Worst idea ever
-Replace Lost Continent with Whoville mini-land (Grinch and Horton) or Wonka or actually add a ride (just something!)I agree there needs to be some sort of ride in this area, but there isn't a ton of space to do it in and make an island close to the level of the others. I'm not sure about expanding Seuss either since the Seuss to LC transition is one of the better ones in the park.
-Lorax dark ride and yearround stage show in Seuss Landing This seems dead in the water, but would've been a good idea.
-Nighttime show For sure.
-Streetmosphere around the whole park Without a doubt, Marvel is the only island you get any serious streetmosphere.
This would make IOA a full-day park yearround (3 major attractions are near empty during winter)