I wish The Miz went back heel. He has a smarmy presence about him that fits better on the villainous side and I've never been a fan of him. Plus, I'd like to see a feud between CM Punk and Miz, which would only work if Miz was heel. I have an idea on how that could get started (could even be how Miz goes heel), and Miz said himself in an interview recently that if he could feud with one guy on the roster of his choice, it would be Punk as they are polar opposites both on-screen and off. I'd like to see John Cena go heel eventually one day but not at the moment. That needs to happen at the precise time in order to capture the magic of it the right way.
For turning baby face, no idea. Cody Rhodes maybe, because I suspect they're slowly building to it between him and Sandow. Seth Rollins too, but I'm not ready to see The Shield break apart yet.