If they can bring back both, great, but I don't think either are going to be the second coming of Chauncey Billups or Joe Johnson--players we're kicking ourselves for letting go years later.
That said, I think it largely depends on what happens on the free agent market. If Dice comes aboard and say Tony Battie gets bought and comes aboard, I'm not sure then if we're going to be all that worried about Big Baby coming back. While it'd be nice to have both Baby and Powe, there's really only room for one of them in a rotation if we actually have real backup centers. If Baby has outrageous contract demands, we certainly could survive with a 4/5 rotation of KG/Perk/Dice/Battie/Scal until Powe came back for the playoffs.