If Lucas hands the directing reins over to someone else, it might work.

Remember, those story treatments for seven eight and nine are probably in his desk drawer, even though he denies they ever existed these days. ;)

Motion capture is getting better all the time, so the sequels can be set just about any period after Jedi. And I'm sure Lucas has seen Tron Legacy, with it's youthful Jeff Bridges doppelganger.

The box office take for the 3D releases will tip the scales one way or the other.