And if I perfect my Quantum Leap time machine so I can enter George Lucas' body pre-1983, here are the changes I'll make to Return of the Jedi:
-Change the (yawn) SECOND Death Star to a new kind of doomsday weapon.
-Change all the ewoks to wookies.
-Leave Leia in the movie as "the other" referred to by Yoda. (After all, she was able to receive Luke's telepathic message in ESB which seems like a pretty good clue to me.) But that doesn't mean she has to be a Skywalker or (shudder) Luke's sister! (And I'm still waiting for the explanation in Episode III as to how Padme gives birth to twins, but somehow Obi-Wan only knows about her son, Yoda is the only one who knows about her daughter, and Anakin knows about neither!)
-So what happened to that love triangle that appeared to be developing in Episode IV? When Luke and Leia talk alone on Endor, have him profess his love for her, but she's confused as to how to respond because she also loves Han. Then after the Death Star explodes and Han asks her if she loves Luke, she finally chooses Solo.
-Have Lando sacrifice himself and the Millenium Falcon (what's the deal with Han's "funny feeling" about never seeing his ship again anyways?) so he can fully redeem himself for being such a dirty, no-good, double-crossing swindler.