I would suppose most coaches use rotations of from 8 to 11 players. There are pros and cons to both ends of that spectrum. You want the best players on the court as much as you can have them there while being rested enough to play full out. That would point toward a short rotation. The farther down the bench you go, the lower the level of ability that is fed into the game. That would say that you keep the starting five in there if at all possible. Media timeouts work in your favor.
However, if players do not have regular game experience, then they are less likely to be ready when you need them, so you need to give players you are likely to need some time in the game in order to keep them game ready. I would assume it is not always an easy decision.