I don't know where the notion come from, that you can only have a certain amount of centers. In a perfect world, all players would be interchangeable , including defensemen. History would tell you, that on the forward lines, centers are the most sought after. The reason is that most coaches play their best players at center, no matter what league you are playing in. I am suggesting that you could have a team of thirteen centers. You could also have a team where you move defensemen up to forward when needed and/or vice versa. My point is that having extra centers is an asset and not a disease you must cure.