Ok, here's what I know is changed from '83 to '97 and from '97 to '04, am I missing anything major? (Improved effects aren't of a concern to me as I don't mind them; and arguably, I really don't have too much problem with the Sarlaac beak.)

Lapti Nek / Jedi Rocks (1997)
Sarlaac beak (1997)
Han commenting on his sight, during the Sarlaac scene (2004?)
Anakin's eyebrows (2004)
The ending (changed both times)

Ideally, I'd need a small amount of 1997 footage to fix this, though, I could do a proof of concept on the 1993/2004 alone.

Moll.