Somebody else in some other thread recently mentioned that they should end Ep3 with Obi Wan at his hut on Tatooine. I think that's a pretty good idea.

But, I think they should end it, and I've said this before, with a tight close up of Anakin's battle scarred face and him breathing through respirators. Then have the Vader helmet lowered on his head from the top of the screen and, when the helmet is sealed, the respirator breathing becomes deeper like that of Vader in the OT. Quick cut to black and the credits and John Williams' famous theme music. Just my two Lincolns.