Nobody is stepping out to guard Miles unless he gets hot. I am a huge fan of his but face it he needs to shoot better outside. If Brewer is in your lineup why would the guys respect the pick and role. You will have 4 players in the lane everytime they run it and that assumes that Miles' man is staying on him.
Basically with very few shooting threats (I don't count the PG as he needs to run the PnR) then how are they going to get looks inside. The only reason it worked (sort of) with Brewer before is because Memo was in the game. Without Memo, Brewer is worthless.