The least objectionable changes were cleaning up some effects. The wholesale additions and CGI shit was not needed. Even then I wouldn't give a shit if they released those "upgraded" versions so long as the unaltered versions were also made available. Doing shit the way Lucas did it sucks, especially when it came to fucking with other director's work. Yeah, chimp face Emperor looks goofy, but it adds to the charm of the series. People loved those movies, warts and all, Lucas shat on them.
Replacing the original Vader actor for Hayden Christianson was fucking stupid. Why did he de-age as a force ghost but Obi Wan and Yoda didn't? He really thought so little of his audience that they wouldn't realise it was Anakin at the end? I know they were made for kids but kids aren't THAT dumb.