What needs to happen is a clear definition of Future World, World Showcase, and Epcot as a whole. As part of this, they can also define Tomorrowland.
Personally, I would like to see Future World gravitate towards the realistic, grounded in science, non-IP vision of the Future and/or Discovery. I'd like to see Tomorrowland be the futuristic representation as explained in Disney movies. This would allow for things like Buzz Lightyear's Space Ranger Spin, Tron and even Wreck it Ralph.
I've also suggested moving not just a re-done Carousel of Progress to Future World but also a re-done Space Mountain. Aside from the exterior building, Space Mountain needs a full tear down and while it's not tied to a movie, it is a pseudo franchise in itself and could be Epcot's first true coaster.
My re-done Future World would have the two Tomorrowland transplants as well as "it's a small world" bridging the gap between Future World and World Showcase as a perfect transition between the two areas.
For pseudo original ideas, I'd like to see Neil degrasse Tyson represented somehow in Epcot, perhaps in a Cosmos based attraction or for a more out there idea - a replacement for Dreamfinder. Sticking with the former (Cosmos based attraction), add in a redone Imagination, the 3 Magic Kingdom transplants and you've got a Future World that should intrigue both the fanbois as well as the casual visitor.
Since I'm throwing out hairbrain ideas, why not continue with Horizons Century 3 and evicting Nemo from The Seas (or potentially closing the Seas entirely). The last thing that I'd really like to see would be a PeopleMover in Future World.
As for World Showcase, I've been a vocal critic of Frozen, but I think characters in World Showcase are unavoidable. So if they can help do it in a way where the characters are addressing culturally relevant things like Ratatouille or Coco I can get on board a bit more than Frozen Ever After.
Sorry for the brain dump.