One of the main challenges of BB is to manage minutes. The way you are proposing would make managing minutes piece of cake. The only aspect of BB that is debatable in terms of minute management are indeed crunch time, where many times the coach makes somewhat stupid decisions, and garbage time, when the team which is losing keeps playing their starters even if they are losing for 100 points. I think we should have a bit more of control of minute management of crunch time and garbage time, otherwise BB is good the way it is.