I have big love for the franchise — I’ve seen Episode IV over 50 times on the big screen — and I think you have a solid ranking. Episode V is my favorite as well. :)
One opportunity I thought they really missed in the prequels was the motivation behind Anakin’s fall and his turn to the dark side.
I’ve always thought that rather than “good vs. evil” that the prequels should have focused on discipline and detachment vs. passion and self-interest. In that way Anakin’s fall isn’t turning to “evil” but rather an inability to control his obsession/love over Pademe. (The darkness could come from his use of the force to manipulate her into returning his affections.) That would be more satisfying to me than all of a sudden “Oh, I guess I am evil and will cut down this children…” It also makes the Sith fuller characters — their motivated by their own self-interests and will use any means to get it rather than solitary figures that spend their free time locked in meditation chambers.
Likewise, Obi Wan’s (and the Jedi’s) failure is a lack of understanding and respect for love, passions and emotions. They’ve become detached from the things that make us most “human” in their sterile ignorance. And it’s emotion — Anakin’s love for his son — that defeats the Emperor, not cold Jedi logic.
And that’s the balance — logic with emotion, analytics with passion, that Luke restores.