At one point, Lucas admits to going back in to post-production and drastically recutting the movie to fit a more kid-friendly Disney-esque media market. Specifically, he was very excited to give Jar Jar Binks a bigger role. I'm convinced there's actually an excellent film laying somewhere on the cutting room floor and Lucas's own vanity was what stole it from us.
Also incidentally, the original New Hope screenplay was a total wreck. His first wife had to completely recut it before shooting began. She became good friends with Carrie Fisher, and Fisher learned the trade of script-doctoring from her masterfully. They both went on to work behind the scenes in a number of popular movies (Fisher even has a cameo in the first Austin Powers, where she tells Austin to quit all the silliness and get to the plot). There's a good reason to believe that Marcia Lou Lucas was the hidden hand that made Star Wars a hit.
That theory missed something that jumped my synapses right at the end. Palpatine killed Vader in order to revive. He pulled the same fucking trick, his love of Vader and his hatred at his betrayal mixed right at the end, and he used it to hitch a ride to his clone stock. Man, fuck, that just ruined the sequels all over again.