The problem with the rotation concept is you don’t get to use them one at a time. Jemison can be an average defender and rebounder, but he’s useless offensively. Theis has a more advanced offensive game, but he’s small. You shouldn’t expect Missi or Matkovic to contribute much this year.

You say there are 5 important things from the center position: Rim protection, perimeter defense, 3 point shooting, rebounding, and passing. Jemison is maybe a slight upgrade in rim protection and an upgrade in perimeter defense, but he’s definitely worse than Valanciunas in the other 3 categories. Theis is maybe a lateral move in 3 point shooting, and a slight upgrade in perimeter defense, but he’s a downgrade from Valanciunas in all 3 other categories. Either way, you’re taking a downgrade in 3 categories.

You can’t simply add Theis’ 3 point shooting and passing to Trey Jemison’s defense and say you got a better version of Valanciunas. You only get to play 1 at a time.

This is the fundamental flaw of the moneyball “replace him in the aggregate” thing. You don’t get to replace 1 great player with 3 good ones, you have to replace 3 players with 3 players. “Replace him in the aggregate” only works if you were starting 1 great player alongside 2 completely useless ones. Then you downgrade the great player while upgrading the 2 useless ones and you don’t lose any performance. But if you don’t have 2 completely useless starters to jettison, you don’t get the full benefit.

Basketball globally might be better, but the reason basketball in the US is so great is because all the money is in the US. Start messing around with pro-rel, and you risk a lot of the income that keeps the top players in the NBA. pro-rel is great for building local interest, it’s not good for keeping money in the league.