I think considering just the center position as being two narrow. I think you need to be able to play two starting quality bigs as your primary rotation, and I don't care if it is two centers, two power forwards, or one of each. Kanter, Theis, Williams are fine to handle one of the two positions (this group is probably more centers than PFs) but we don't have anyone for the other needed position (Ojeleye, GWilliams, etc are barely NBA players).
We can't afford to overpay for the position though. We are going to have to pay all our wings top money, there isn't going to be much left for the bigs, unless we move Hayward.