Having the 3 directors (Kasdan standing in for RoTJ) would seem to be proper way of doing it - though if one of the other 2 were critical of GL in some way is GL the type of bloke to allow it on 'his' set? Or would it be edited out etc? Would the other 2 be ok with that, or demand that they are shown in full or not at all?
Having the 'Lost Cut' on there too would be great - though the amount of cut scenes GL has held back from Eps 1 & 2 on their dvd releases gives me the impression that there won't be - unless GL is planning some sort of bumper uncut scenes dvd to ocme out in a few years time. More likely is that there will be more tinkering with all of the films in the next batch of whatever edition GL is going to release in a few years - OR - that he deems the unseen stuff as unnecessary or unworthy and we'll only get to see it drip fed through his pay-net Hyperspace service, a la the failed Jedi mission to the control ship in AOTC.
With less than 2 months to go GL or his staff have let specualtion build as to what is on the latest set - how long they can keep the wall of silence going for is yet to be seen - personally I think the silence tells us not to get our hopes up... there is still more tinkring to come.