Well i wonder the same.
I want to have 3 big guys. A Center, a PF and a C-PF. So lets say player 1 is C, player 2 is PF, and player 3 is a C-PF
i use to do it like this
C Starter: player1 Backup: Player3
PF Starter: player 2 Backup:Player3
So even if player1 and player2 start together, there will be multiple times where Cplayer1 & PFplayer3 and also Cplayer3 & PF player2 will play together. This barely happens... Last time i tried it, player3 played 15 minutes and was almost all of them as PF, my C played 46 minutes lol.