With the starters set, i honestly see this as a battle for rotation spots instead of straight positions. Posey last year wasnt necessarily our best 4, but played there a lot b/c he was our best option.
Coaching involves finding your best players, and putting them in the best position to make plays. If your 8 or 9 best players are guard heavy, play small and adjust the offense.
That said, i believe our best players are
Rondo
Allen
Pierce
Garnett
Perkins
House/Giddens
Walker/Tony/Miles
Powe/BBD/O'bryant
Guards - IMO, House is a lock for first guard off the bench. Sam can be used as a spark or change up in case of an off night or for matchup reasons. And Tony can be used as a defensive guard against tough matchups. Giddens will learn and has a chance to challenge tony later on. Pruitt is talented, but is approaching the point where the 'big potential' better start to at least show through a bit.
Swing - Here is where the real battle is. Miles/Walker/Tony will compete for the swing spot. I'd give the edge to walker, but tony and miles bring the ability to play multiple spots. I'd look for miles/tony to contribute early and walker to work his way into this spot by year end.
F/C - Obryant/Powe/BBD Much like last year, we have BBD and Powe who are energy guys and will improve this year. They also have the ability to fill in at the C if needed, but have some matchup problems where length will be needed. Enter Obryant. I look for the same rotation as last year based on matchups. How they all 3 will play during the season will cement who will be used during the playoffs.
I think unless there is a deal to move one or two players, the real decision to cut someone will come down to Pruitts play vs scals expiring contract. As of now, i'd say scals expiring contract is more important sadly.