It's really tough because what players are asked to do from era to era is so different.
Centers: Bill Russell, Kareem, Mark Eaton, Olajuwon, Dikembe, David Robinson and Ben Wallace were all dominant in their eras, but often for very different reasons. You could almost put Gobert in that category now too.
Forwards: Rodman, Garnett, Duncan, and Draymond were all game-changing forces, but again with very different games
Wings: Artest, Kawhi, Pippen
Guards: Bowen, Tony Allen, Payton, Cooper, Jordan
That's 20 right there. How can you even compare them to each other?