It takes a lot of the "What If" out of things when most of the best players are from recent times. I think that Bill Russell is vastly overrated historically and all of his teammates are very underrated, but it's even worse in the sim where Russell is not better than many modern guys defensively, and far worse than most modern big men offensively. I am surprised that he was even drafted in this league. He is a top rebounder, but there are several modern guys around the same level as rebounders.
Based on my formula of Career Win Shares, plue best 7 seasons of win shares, divided by 2, and then adding in career Playoffs PER, Russell is the 7th most valuable center ever, but he's nowhere near that in the sim. Here are my rankings:
Kareem - 228.52
Wilt - 222.13
Admiral - 170.16
Shaq - 167.89
Gilmore - 164.84
Moses - 157.55
Russell - 152.61
Olajuwon - 150.08
Issel - 138.40
Mikan - 137.19
Dwight Howard - 132.95
Parish - 126.02
Bellamy - 125.62
Ewing - 123.31
Lanier - 117.52
Mutombo - 110.53
Beaty - 109.12
Jokic - 107.61
Ed Macauley - 107.51
Bosh - 105.77
Johnston - 105.65
Unseld - 105.60
Sikma - 104.59
Gobert - 103.56
McAdoo - 102.88
Laimbeer - 101.33
DeAndre Jordan - 99.46
Horford - 99.18
Chandler - 97.40
Mourning - 96.15
Ben Wallace - 96.10
Cowens - 94.34
Divac - 92.00
Willis Reed - 89.79
Marc Gasol - 89.68
Larry Foust - 88.42
Marcus Camby - 82.27
Thurmond - 80.15
Of course the guys here who are still playing will continue to accumulate value and move up the list. Jokic should be top 10 easily when he retires.