Well any attraction that has been replaced - I have enjoyed the newer attraction better. I definitely enjoy Mission: Space and Test Track more than World of Motion and Horizons. As much as I adored Mr. Toad, Winnie the Pooh is a really great, immersive ride. Here's my "sort of" list...
1. I would bring back Alien Encounter, but that would just be one more attraction my kids wouldn't be able to visit with me, and I have more fun when they're having fun with me.
2. River Country was fun, but it had nothing on the newer water parks. It would be REALLY cool to revive that as part of Fort Wilderness though (no admission needed).
3. I really, really miss having a real Dreamfinder with his little figment puppet outside of JII. The ride in it's current state would be fine if instead of that idiot Eric Idle, they just had used the Dreamfinder. And the current imageworks stinks. I miss the old one.