I agree with others -- the Bulls aren't doing anything of consequence this season, even with a recovering Rose on the floor.
Derrick should just call it a lost season and aim to come back next season completely strong and healed.
Luckily, I think we can reasonably expect Rondo's injury to take much less time to recover from. As others have said, there's a significant difference between a partially torn ACL and a torn ACL, MCL, and PCL. Rose basically blew out his entire knee. Rondo's injury, while severe, is not on that level.
I say all this, of course, based only on what we've been told and from what I know of these kinds of injuries (which admittedly isn't a ton).