NBA Efficiency Rankings

NBA's efficiency rating: (PTS + REB + AST + STL + BLK − ((FGA − FGM) + (FTA − FTM) + TO))

Performance Index Rating: (Points + Rebounds + Assists + Steals + Blocks + Fouls Drawn) − (Missed Field Goals + Missed Free Throws + Turnovers + Shots Rejected + Fouls Committed)

I have started digging into the data after looking at the All Time Ratings that you posted..
It is a fun statistical reference, but as the original author has said it has flaws and is based on too much offense. 

I think this will be fun to see if we can figure out a way to include a better feel for DEF vs OPP with League numbers included. 
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One glaring error on the historical side is the numbers from Blocks/Steals/Turnovers prior to 1973.
The primary hole in the formula is with none other than Wilt.

By all accounts that I have ever read, it is safe to assume that he averaged over 6-8 blocks per game. Most historians have documented the incredible number that he blocked.  When you include the fact that he was quicker than the small forwards it is safe to assume that his steal number would be above the league numbers and even Kareem average 1 a game.

Using Wilts Career 30pt + 23RB + 4.4ast+ 6 blocks + 1.6 steals = 65
Less
 (22.5-12.1) 10.4 + (11.4-5.8) 5.6 + TO 2.7)  TO is Kareem number. =18,7
 65-18.7 = 46.3

Wilts Career on NBA efficiency 46.3. 

Jordan
30.1 + 6.2 + 5.3 + 2.2 + 0.8  = 44.6 
11.5 + 1.4 + 2.7=15.6
44.6- 15.6= 29