To give a list of projects that seem to be in development...
USF
Secret Life of Pets - Replacing Shrek 4D
T2 Replacement - Replacing Terminator 2 3D
Ministry of Magic - Replacing Fear Factor Live
Fast and Furious: Supercharged - Replacing Beetlejuice and Disaster
Super Nintendo World (Mario Kart, Donkey Kong, Yoshi) - Replacing Kidzone {Excluding ET and Squarepants Store}
IOA
Forbidden Forest - Replacing Dragon Challenge
Volcano Bay
Expansion is in the cards, as it was confirmed via a CNN Article before Opening Day. Just depends on when, not if.
Hotels
Adventura Hotel - Land right next to Sapphire Falls and the VB Drop-off and Pick-up right at the park
Dry N' Tame - Replacing WNW Waterpark and Parking Lot
USF does seem to be getting a Magic Kingdom vibe. I really hope that the eventual 3rd gate becomes the real Magic Kingdom of Universal. None of Universal's parks have the facilities for a good nightime show (IoA doesn't have enough room for seating by the lagoon and the lagoon paths are in weird places / bad views) or a decent parade route.
Excluding hotels- which are relatively different in design, construction and planning vs theme park attractions- More than any of the attractions mentioned, they Have bigger needs. All of those attractions seem badass- including HTTYD if we were to add that. They all get me excited. But we can't miss the forest for the trees.
IoA- but even moreso- USF, desperately needs two things more than any of those single attractions (sans Nintendo which will print money)- a nighttime offering and better food offerings.
Food:
They need to step up their QS and TS games at both parks and get more on par with Disney. Potter is the best QS at either resort, but the drop off is massive from there. Epcot has a dozen+, DAK and MK both have significantly better TS and QS than UOR as well. The disparity there needs to narrow. Disney is only expanding their lead with the likes of Tiffins, Pandora and soon to be the space restaurant. Meanwhile, we're getting a King Kong snack cart. Missed opportunities galore. So while these attractions are great- if we don't get some good and unique food with them (sans nintendo which is obvious), it won't be what it should/could be
Nighttime offering:
It sucks currently. As in, it's atrocious. As in, has anyone ever watched it twice. As in, how many people do you see leave halfway through on a nightly basis.
Potter castle won't be enough.
Make nighttime special. Make the park as a whole more complete. Dining and Entertainment will create that more than any attraction would.