Well, the emperor from ESB had a smooth voice and seemed self-assured in an extremely calm way. He had no need for boisterous taunting or cackling like some cranky old pervert. It was very cool. Then Jedi changed that dramatically. We got the cliche asshole who was took fiendish delite in spreading evil. I'm not saying that Jedi's emperor was bad, but Empire's was better.

Either way, in terms of the SE, there wasn't that big of a difference between the two emperors to justify erasing one. I have saved myself from watching the 2004 SEs so I have no idea what the dialogue changes are. In the end, its just another perfect reason why the original theatrical releases should be available alongside the SEs at the very least.