And Bail Organa.

I always thougth the best way of doing RETURN OF THE JEDI was doing a pararel story. Kinda like the Godfather 2. After the revelation at the end of ESB it was time to sit and explain what happened in a simple way.

So you would have the main plot for ROTJ (rescuing Han, destroying the Empire, bring anakin back) surrounded by this two stories that would tell a similar story, both of them with a three character relationship (Luke-Han-Leia, Anakin-ObiWan-"Padme"). Both of them having the main character being tempted by Palpatine.

So you would only need to explain the main parts of the "prequel" plot, how ObiWan and Anakin meet during the clone wars, how Anakin marries and finally how he is tempted by the dark side and hates ObiWan (maybe because padme?)

No brother-sister, no ewoks, and more Obi Wan.

EDIT: Oh, and NO Death Star II. Give Palpatine something really evil and powerful. Like some device/holocron/magic wand, that will make him able to control every single being of the galaxy. Something he needs to control by himself and not leave some Tarkin/Vader handle. Something like that would make the whole galaxy to rebel against him, so it wont be just the alliance vs the empire, it would be good vs evil again.