Seeing as it is simply a repackaging of the SE's, lets discuss what's not on the SE's:
A New Hope is missing a few alternate takes including an alternate End Titles.
Empire is missing the alternate "Rebel Fleet," "End Credits (Film)" and the film ending to "Luke's Nocturnal Visitor."
Jedi is missing... god where to I begin:
~ 90 seconds of score
~ 6 second Ewok Forest Battle Insert
Lapti Nek Versions (film, film instrumental, album, extended album, album instrumental, english)
Unknown Source cue
Max Rebo Band Songs 1 and 2
Alternate Leia's News
Yub Nub (Film, Ewok, Choir)
Jabba the Hutt's Suite (original recording)
So again, they are in no way complete lol...