I mean, the team needs a backup PG for sure...and a 3rd big (probably PF) who can be a main part of the rotation with JV/Amir, and a 4th big who has C size but isn't immobile like Gray. Gray and Acy are good as bruising/hustle 3rd stringers.
The team has to turn Bargnani into at least a backup PG or 3rd(whether he or Amir starts) big. Then use the MLE to get whatever is missing.
I know if it came to PFs, my #1 MLE target is Carl Landry, if he opts out. If he doesn't, I might actually not bother using the whole MLE on someone. Maybe try to get a couple of depth bigs from guys like Brand, Wright, Clark, Hickson, Turiaf, etc..
I'm really digging Mo Speights as a 3rd big or starting Pf. Or someone like Brand or Jefferson who can smash dudes around in the paint and grabs some boards.