If I had carte blanche, no-holds barred access to all the previous releases (and even the Lucasfilm archives), it would include:

Disc 1:

Episode IV: ANH - Original Theatrical Version (New 4K Print)
Original Dolby/Mono Mixes
Three new commentaries:
- Hamill, Fisher, Ford, Mayhew, Daniels, Baker (Track 1)
- Lucas, Kurtz (Track 2)
- Burtt, ILM Staff (Track 3)
Audio commentary from Definitive Collection laserdisc
Audio Commentary from 2004 DVD
Isolated Score
Original Teaser Trailer
Original Theatrical Trailer
Deleted Scenes from "Complete Saga" Set
- Full "Human Jabba" Sequence

Disc 2:

Episode V: ESB - Original Theatrical Version (New 4K Print)
Original Dolby/Mono Mixes
Three new commentaries:
- Hamill, Fisher, Ford, Mayhew, Daniels, Baker (Track 1)
- Lucas, Kurtz, Kirschner (archival) (Track 2)
- Burtt, ILM Staff (Track 3)
Audio commentary from Definitive Collection laserdisc
Audio Commentary from 2004 DVD
Isolated Score
Original Teaser Trailer
Original Theatrical Trailer
Deleted Scenes from "Complete Saga" Set

Disc 3:

Episode VI: ROTJ - Original Theatrical Version (New 4K Print)
Original Dolby/Mono Mixes
Three new commentaries:
- Hamill, Fisher, Ford, Mayhew, Daniels, Baker (Track 1)
- Lucas, Marquand (archival) (Track 2)
- Burtt, ILM Staff (Track 3)
Audio commentary from Definitive Collection laserdisc
Audio Commentary from 2004 DVD
Isolated Score
Original Teaser Trailer
Original Theatrical Trailer
Deleted Scenes from "Complete Saga" Set

Disc 4:

Episode IV: The Lost Cut (Restored Print)
New featurette on discovery/restoration of Lost Cut

Disc 5:

Definitive Laserdisc Collection Extras
The Making of SW (PBS Special)
The Making of ESB (Parbot)
2004 DVD Extras

Disc 6:

Complete Saga Extras (OT)
New documentary on history of franchise/cultural impact
Return of the Ewok (Full Version)

Disc 7: Expanded Universe

Dark Horse SW comic cover gallery
SW books cover gallery
SW commercial archive (ALL commercials/tie-in commercials from 1977 onwards, not including PT commercials)
SW Casting Auditions
SW Cast Appearances (ALL appearances from 1977-1983)

Disc 8: Star Wars Holiday Special

Original Television Broadcast (upconverted)
New commentary (Lucas/Ford/Fisher/Hamill...LOL)
Concept art
Retrospective featurette