In my opinion, whatever you fill in with your imagination cannot help but be 100X better than what actually happens on the screen in Episode III. The film just mechanically moves the pieces around to bridge the awkward chasm between where things end in II and the completely unrelated beginning of IV.
Which is not even necessary. It’s absurd that nothing happens for twenty years.
Vader’s suit looks exactly the same? They dump Luke on Tattooine why? Having Luke and Leia be siblings was fucking stupid, but if they had to do it, the scene in VI where Leia remembers their mother was a pretty good scene. And Episode III just flatly contradicts it.
Skip straight to Return of the Jedi. But like, these are just crappy movies. Do what you want.
Star Wars and Empire Strikes Back are not crappy movies ;-|