It wouldn't make sense to me to retread old ground and remake films that are barely a decade old. The prequels are what they are, they might not be universally loved but they're the story Lucas wanted to tell and, like them or loathe them, he told the story the way he wanted. Personally, I can't see anyone beside Mark Hammill as Luke Skywalker or Harrison Ford as Han Solo and it would be particularly hard for the fanatical SW fanbase to accept such changes. It might be possible but it would be pointless; why would you remake Empire Strikes Back?