If it were up to me, this is what I would do for the future of this park over the next 10 years
There’s going to be expansions to each of the lands at Epic Universe as well as two new portals
Here’s what I would do for each
Fully indoor Luigi’s Mansion attraction, with an indoor queue for perpetual darkness and midnight, and have a reveal of the haunted mansion that rivals the ministry reveal. Make the ride a trackless shooter ride.
Indoor Quidditch Story-Coaster - Harry Potter lands print money the longer people stay in them, give Ministry land a second attraction to spread the crowds from Ministry of Magic, and ensure people spend more time in the most beautiful land ever built. (Vekoma Thrill Glider)
Add two flat rides to Celestial Park, one in front of the hotel, and one near the entrance to Super Nintendo Land.
How to Train Your Dragon Simulator - go full fop, fly through the Isle of Berk, changed slightly with the epic universe rides added, include exploration of the hidden world and flying above the clouds. Make it high capacity and fully indoors, and not incredibly intense (Flight of Passage Type Ride)
Donkey Kong Country logflume - build out a gigantic banana boat log flume that expands Donkey Kong land, taking advantage of waterfall already there, tie the water through the whole land together to feel like the rides almost blend together, and then an outdoor quick service restaurant with a mini-tiki bar, serving banana floats with alcohol options.
Creature of the Black Lagoon boat ride with an outdoor swamp-land introduction section that can be skipped when the weather is poor. Underwater animatronics, a mild drop or two, and a spooky queue (Mack Rocking Boat)
After this 10-year plan, build two new portals for Lord of the Rings & Legend of Zelda. A major thrill coaster would be included in one of these plots by either Intamin or Mack Rides.