ROTJ Disc 2, Track 5 (Battle of Endor I) could be a college music theory semester by itself. And another semester on orchestration. I've transcribed most of ROTJ over the years, and this 12-minute piece alone has more raw ability in it than the entire PT, and more than just about every blockbuster of the last 5 years I can think of put together. ESB and definitely ANH, too, were scores on levels you basically don't hear anymore. Ditto most of his work from his "Golden Period."