Unless we have exceptionally versatile players, usually we need 4 guards, 4 forwards and 3 centers. Yes our guards are, to an extent, interchangeable. But as we've seen the last couple years, it really helps to have a true PG that can run the team, get into the lane and make other players better. FH is now playing that role .. but it took a couple years. Sure, Tyus could bring the ball up to take some of the pressure off. But that doesn't make him a PG. Frank also could play off the ball (in some ways this suits him better). HW did his best to sub in. But we had no real backup at SG. So having 4 guards (2/2) is the right number unless we want to have our shorts in a bunch all year like we have.
Forward is also interchangeable, to an extent. We can swap a big SG for a forward ... but we pay the price. Our rebounding margin finally went positive this past year b/c we had long guys that could rebound at both forward spots and a 7-footer in the middle. It makes a difference. Unfortunately, bigs pick up fouls like ants on sugar. With only 2 centers, one gets hurt or BOTH pick up fouls, now you're swapping in forwards (MD) and taking a hit. So 3 centers is not really a luxury ... it's smart roster management. Forward you cheat disaster with 3. But 4's the right number -- with only 3 if one guy gets hurt you're SOL with no backup.
That's 11 minimum. Not counting walkons. We've had our shorts down so often the last few years we forgot what depth was. That's about to change this week.