I would just do something similar to the Blade Runner 30th Anniversary Set, but one for each saga movie. Each version of the films restored in HD 1080p with 5.1 audio
Original Structure:
Disc 1: Theatrical Cut (1977 / 1980 / 1983)
Disc 2: Special Edition (1997 & 2004)
Disc 3: Blu Ray (2011)
Disc 4: Bonus
Prequel Structure:
Disc 1: Theatrical Version (1999 / 2002 / 2005)
Disc 2: DVD Version
Disc 3: Blu Ray (2011)
Disc 4: Bonus