Personally, I see it like this, and I don't know how it could be any other way.
Perk, Wallace - 30,18
Garnett, Davis, Wallace - 30,11,7
If we give Williams any of those minutes, it'd be hurting us more than helping. We might see him get 5 or 10 minutes on nights, but never on a consistent basis (and probably in garbage time or during foul trouble). I think Doc will give Scal minutes before Williams. Just his experience with this team speaks enough.
Any talk of giving Davis, or Scal, or KG minutes at the 3 seems highly unlikely.