True, but there were miscastings and bad characters
all throughout the prequels. Lucas doing it all on his
own shows all his flaws in writing and directing. The
best SW movie by critics, ESB was not directed by
Lucas but Irvin Kershener IIRC.
All I am saying is that Lucas had some good ideas,
but needed others to tell him "This won't work out"
"This is campy", rewrites, and so on. The prequels
could have been cool even though you know what
was going to happen.
Empire is by far my favourite, but there are bits in Jedi that I love too. Anything OT with Yoda in it is golden, and the reveal and eventual redemption of Vader, including the whole battle of wills on the Death Star II can still give me goosebumps if I'm sufficiently involved in the story at the time, but if for instance someone had never seen any of the films, but wanted to watch one, and could only watch one for some reason (they're being executed for posting a pic they don't hold the copyright for on a website or something) it'd be Empire, no doubt.
I've watched quite a bit of the Making Of stuff on the DVDs for the films, and of course, there's more available for the prequels, so it's not entirely clear exactly how everything happened first time around. Many stories are after the fact, and of course, I'd imagine there's something of a reluctance to have people with conflicting memories or opinions on your anniversary DVD editions. BUT, the impression I get about the first 3, is that they made the films Lucas wanted to make, with changes along the way, as and when things could or couldn't be done.. By the time we get to the new ones, he's got enough money that he probably could have got a young Alec Guinness to play Obi-Wan if he wanted to, through CGI trickery or pacts with dark gods, so there were few times he had to really rethink himself. Another thing, similarly, creative stuff...all I know of pre-production character designs on the first tilms are the Ralph McQuarrie paintings. Like effects for story set-pieces I imagine that what was originially asked for was filtered through a few people first, and even then still subject to what could work physically. It seems as well, from hearing Lucas himself talk about the films, that first time around he had ideas for what he wanted to see, but by the time the prequels roll around he's saying "we need an alien. a bad alien" and going into a room with hundreds of vaguely different drawings by, admittedly very talented people, and he's just rubber stamping, or sticking a gold star on them to say they're good. There's no-one else to suggest that something might not be a good idea, nor does it seem the man is even all that invested in the thing.