I would've killed off Han Solo (as Harrison Ford suggested) for dramatic impact by Jabba the Hutt. I could just picture Han Solo hanging from a noose, dead, and then it would cut to a shot of Jabba laughing. I think that would've been a great way to raise the impact of the whole movie, and you would really build up hate for Jabba. Lando would get killed in the final battle (saving someone's life), the Ewoks would be gone, and there would be no Death Star II; that's too redundant. I'm not sure what I'd do to replace it, but it should be a lot more surprising and unpredictable. The confrontation between Vader and Luke should have been much more violent and fierce; Luke should have deeply wounded Vader and agreed to sit at the Emperor's side as his apprentice. Then, as if in a trance, he should have gone up to some kind of control panel and destroyed a huge ship in the Rebel fleet, laughing evilly. Then, eventually he should shake off the trance (kind of like in The Temple of Doom), turn back to the good side, get nearly fried by the Emperor, and be saved by Vader, his father (as it was in the movie). Leia should not have been Luke's sister; it would make it much more frightening knowing that Luke was the last hope and that he had turned to the dark side.