Wasn't there some passed on idea in the EU about having someone putting on Vader's suit or something? I think it's a bad idea, just like I think resurrecting Vader is a bad idea. We saw him on a pyre in ROTJ and then as a Force Ghost. With Maul, at least they had the wiggle room of not seeing his corpse.
Let the character die with some honor and dignity, and just create new villains. I hope this is just a rumor, but if it isn't, this project is already in trouble. They might as well just adapt the Thrawn trilogy, Dark Empire, Crimson Empire, or the New Jedi Order.