If this is an Ultimate Set why not have everything even if it is identical.
(which none of the releases are as each has some thing applied to it (often minor and imperceivable) which tweaks the film to fit the release medium)
one of those five really potty-mouthed guys
People like myself don't deem certain words in language as offensive, so if you can remember who from PvsG are you talking about, please clarify.
For me the idea of a Disc Set, let alone an Ultimate Trilogy Set, is outdated. Just make all the versions and variations purchasable online. If I want to watch the 1985 RotJ in Spanish with Korean subs, let me do that.
Generally on changes between versions there are many threads in these forums attempting to identify them. Unfortunately not one resource listing them all. So if you poke around some of your questions can be answered from threads like:
Opening day 1977 3 audio versions info: http://www.fromscripttodvd.com/star_wars_a_day_long_remembered.htm
ESB 70mm/35mm changes: http://originaltrilogy.com/forum/topic.cfm/Complete-Comparison-of-Special-Edition-Visual-Changes/post/537626/#TopicPost537626 (you probably don't need a full second disc for this, as the visual changes are few and the audio changes might not be that long of a list) http://originaltrilogy.com/forum/topic.cfm/ESB-70mm-Soundtrack-1980-in-theatre-recording/topic/12501/page/1/
On RotS: there are more changes in the 2011 then just the wipe: http://originaltrilogy.com/forum/topic.cfm/DIF-Difference-tool-to-spot-visual-changes-SW-2004-2011/post/536882/#TopicPost536882
and new things found like 1977 credit changes: http://originaltrilogy.com/forum/topic.cfm/Credits-Leaders-Thread-was-Star-Wars-Pre-Re-release-Credit-Change-June-77/topic/12960/
The Phantom Menace had the alternative opening day version where Maul is not cut in half. There also might have been differences between the film and digital version. There were changes between the digital and film versions of Attack of the Clones. Attack of the Clones also had an IMAX edit which people have mentioned liking.
This thread is similar to: http://originaltrilogy.com/forum/topic.cfm/Star-Wars-film-versions-and-best-DVD-sources/topic/6126/