It won’t happen, but after hearing about the MGM Grand theme park, I would love for Vegas to try a theme park again. Would love to see a smaller scale version of those indoor parks they have at Dubai up there.
Again, I know it likely won’t happen, but I think the best case scenario would be to gut Adventuredome and start new. They can have a roller coaster that goes outside of it (Think Manta at Sea World Dubai).