Honestly, what was REALLY changed in the OT only to match with the PT? All I can say is Hayden Christensen and Boba Fett's voice. Nothing else. It wasn't possible to have those two things back when the movies were made, so obviously they had to be added, and IMO the movies as a whole saga (the only way they should ever be watched) are better for it.

Everything else was only changed to better the effects/ restore to his original vision. This would have been done (and was) even if there never were any prequels.

I challenge people to find other examples than the two I listed above that were changed ONLY because the prequel trilogy exists. The Emperor thing I don't count, (maybe the dialouge..?) because it should have been the same dude from RotJ all along.