Sixcess said:
But... for me it sags a bit in the middle. Yoda doesn't really come into his own until the prequels and so in Empire he's mostly just a slightly annoying muppet, and the end is uneven in that while Luke gets the aforementioned awesome confrontation with Vader, the rest of the main characters just run around blasting a few stormtroopers.
This paragraph, I think, summarizes your problem understanding people's appreciation for
Empire.
Yoda: Muppet >>>>>>>>> CGI, - any place, any time. Yoda jumping around looking like a video game in
Clones was the stupidest thing in the whole series. The whole point of him being a feeble little muppet was to show that the power of the Force was spiritual, not physical. Yoda should
never have been shown to hold a lightsaber because he doesn't need one.
"Your weapons. You will not need them."
This is one major point that draws a lot of people to favoring
Empire. We get small glimpses of telepathy and mind-control in the first
Star Wars, and Vader and Obi -Wan talking about it solemnly, but it's mostly treated like a super power (though not to the degree of the prequels). It's
Empire that establishes what the Force really means, and not just in the tiny fictional universe of Star Wars, but on a real, relatable, human level. It took the fun, pulpy, adventure story that Lucas laid out in the first film and turned it into something meaningful. And it's through Yoda that we learn all these things - he has no "coming into his own" to do beyond that.
As for the second part, the rest of the main characters shouldn't be doing much more than running around shooting bad guys at that point in the film because that would upset the balance of drama. Those characters and their plotline already hit their emotional peak when Han was frozen, and if it kept rising, it would interfere with the emotional peak of Luke's fight and Vader's reveal. Leia, Chewy, and the rest fight a battle that slowly becomes more and more hopeless, and clinches out just as the Luke/Vader fight starts to wrap, letting the audience sink into the realization that this movie isn't going to have as happy of an ending as the last one. It is one damn well-constructed sequence.