I agree, a second Death Star is weak, but they could have carried that off. It seems like destroying it, killing the emperor, and having Darth Vader die wouldn’t be quite enough to spell the end of the Empire. Sure it might have turned the tide in the Rebels’ favor by having cut off the head of the empire as such, but they portrayed it at the end as being too much of a final victory for my taste.
If we take the expanded universe as canon, we later find that not only did the empire remain a force to be reckoned with for some time, but we find that Palpatine has an endless supply of clones of himself. That rather renders the victory in Jedi moot.
If we just go with what we’re given on screen, then there are still quite a few star destroyers and stormtroopers to be taken care of. I’m pretty sure that it wasn’t just having the threat of force lightning and force chokes hanging over their heads that gained their loyalty. I got the impression that the empire was just that: an empire, and one that was big enough to survive the losses that they took at Endor. After all, they sure seemed strong enough after their defeat at Yavin.
Whatever the case, there was still a lot of work to be done after Jedi that they seemed too blissfully unconcerned with. Maybe portraying the empire’s search in ESB as an act of desperation on the part of a badly crippled dictatorship could have set them up for explaining why the defeat at Endor really did mean the end of the empire. It wouldn’t have made for a very exciting movie if they’d discussed in detail the economics of having two Death Stars getting eradicated along with all the manpower on board, but perhaps if they’d just given a friggin’ NOD to that possibility, it would have helped.
On the whole, perhaps it would have been better if it had been darker (and I don’t mean having the Millenium Falcon get destroyed; that would have just amped the level of suck, much like killing off Trip in Enterprise did). It seems to me like they just wanted to take care of rescuing Han Solo and then wrap up everything else with a tacked-on happy ending, quality be damned
Perhaps if the Ewoks really had been Wookiees with some level of technology beyond a bunch of bullshit gummi-bears hangliders or stone age weaponry, their victory over the Stormtroopers on Endor would have been more credible. Instead we have a bunch of cute bullshit.
And cute is the much more visible downside of Jedi than the Death Star/assassinated head of state problem. Aliens are nice. We got a good sampling in the original Star Wars at Mos Eisley with some rather clever concepts. However, Jedi just had too damned many that were too damned stupid looking. It’s as if the only species at Jabba’s palace of which there were more than one, aside from humans, were those stupid Gammoreans. And on that note, anthropomorphic animals make shitty aliens, in my opinion. That’s one universal complaint I have about Star Wars since Jedi: they have an inordinate number of ill-conceived alien species. Much like the excessively busy space battle in Sith, it becomes too much to process after a while.