Regarding the Emperor, both 1980 and 2004 versions have problems. The 1980 version doesn’t look like the ROTJ Emperor whilst the 2004 Emperor also looks different to the ROTJ Emperor. Even though it’s the same actor, both his appearance and acting don’t really match what we see in ROTJ.

So for me, neither one really matches up with ROTJ. But at least with the 1980 version, it’s the original one. Despite it later not making sense, there’s something to be said about watching the pure 1980 TESB without thinking about later movies. With the 2004 Emperor, all I’m reminded of is a prequel movie.

With all that being said, I would have mostly been okay with an Emperor change done the way Adywan did it: https://www.youtube.com/watch?v=h0q0CF5Y1cI
At least that Emperor looks like he does in ROTJ. Maybe the acting is still a little stiff but I like it better than what we got.