When O'Quinn and Williams come off the bench its like a punch to the face to the other team, they make their presence known. I really like seeing that from the second unit, teams will know they cant let up when the starters sit, things might get even tougher.
Two players who need the most time with KP IMO, are Melo and Grant. If KP does sit, at least Grant and Porzingis would get more PT together. I believe that Melo and KP should get used to playing together and find a way (the sooner the better) where they can both have an impact as teammates.