I would not remove Death Star II. It’s iconic, it’s something that’s a big part of Star Wars, like it or not. I mean, it’s even the logo for this website.
As a general rule, I wouldn’t remove things people expect to see when they watch a certain Star Wars movie. That includes major characters, settings and plot points. Like, if it would be on the poster of the movie, leave it. Jar Jar, ewoks, DSII, Star Killer Base, etc.
I beg to differ, with an entire saga edit we have the ability to omit certain things most edits cannot. For example, if we wanted to make the republic troopers not clones, and just drafted citizens fighting evil droids, we could remove any instances of “clone” in the PT and cut the line about the Clone Wars from ANH. That’s something most prequel edits cannot do, and while I’m not saying we should do it it’s something to consider.
I don’t want to narrow the focus down too much, but as a counter to your examples:
I think Ewoks are too ingrained into the story of ROTJ to remove. DS2 is iconic but stupid if you think about it, I can see both sides. Jar Jar is universally hated, I don’t think anyone would oppose from his omission (if we could pull it off). Death Star 3 needs to die.