Just wanted to say that this is a really good description of exactly what was wrong with ROTS: You just didn't care. (At least not much). You kinda care 'cause it's Obi-Wan and Luke's dad and Yoda up there, but aside from that....it's like Lucas thinks in his mind "Oh, everyone will be so stoked to see these characters again and that climactic battle between Anakin and Obi-Wan...who needs dramatic tension? It's already there!" You know the whole time how the whole thing is going to turn out (which is major weakness of the prequels, but one that might have been overcome had Lucas provided any genuine insight into the story itself) so a writer/diector needs to work pretty hard to make you care.Now let's look at the battle on the lava world at the end of Return of the Sith. Throughout the fight, despite the fact that we are told that Anakin's supposed to be one of the strongest of the Jedi, you don't really see any clear victor during Anakin and Obi-wan's chaotic struggle. Despite all of the foreshadowing that Anakin was going to be some ultimate bad guy, Obi-wan never seems to be at much of a disadvantage. Then they stop fighting all together, losing any tension from the seen that had built up in the scene, if any, and Obi-wan says how he has the higher ground, and if Anakin attacks him Anakin will lose. Then Anakin attacks him anyway and loses. Lame! Where is the increase of jeopardy for Obi-wan? Where is Obi-wan certain to get defeated to make us get on the edge of are seats worrying about him? Where is the miraculous and unexpected twist of fate that allows Obi-wan to narrowly escape death and gain the upper hand? I'm sorry, but it's just not there! Obi-wan cuts down Anakin as easily as a food processor dices a head of lettuce, and doesn't even lose his breath while doing it. The control of tension for that scene was so poorly played out that I doubt Lucas even bothered to storyboard that sequence at all.
OF COURSE we know that Obi is going to make it (otherwise how could he show up in Episode IV?) so there needs to be some genuine tension. There isn't.
Another thing is Anakin's character. We felt some real sympathy for him at the end of Jedi, seeing him trapped in the suit like that after he'd saved Luke's life. There is very little, if any of that in the prequals. Anakin, or rather Lucas, never reveals what the heck is going on in this guy's mind.
Oh--Anakin is cold and scared...that must mean he misses his mother which must mean that he's sad which means he's afraid which means he's angry which means.....Thanks for that Yoda. There's no way anyone would have figured this out without Yoda's helpful insight. That terrible "yippee!" dialgoue certainly didn't help.
Anakin is mad at Obi Wan because....Obi basically raised him from a child? Helped free him from slavery? Helped him develop his powers? Supposadly Obi is this overbearing guy....but we never SEE that. That's one of the reasons that Anakin is so unlikable, because his grievences seem to spring from nowhere.
Anakin loves Amidala because....she's hot? That's about the extent of my knowlege.
Anakin's mother's death is the reason for his plunge into evil? He was away from her for ten years and suddenly one day it occurs to him to check up on her? Where was he before that?
Anakin wants to save Padme but somehow ends up killing her. I was definetely lost with this one. "Obi-Wan turned against me....don't you turn against me!" Huh?
The script is more like an outline for a film, not a real screenplay. As a writer there is no worse gaffe than "telling" instead of showing, but Lucas does it all the way through. If he'd been a novice filmmaker trying to get into the biz and came in with a script like this, he never would have made it.