Excellent post. Obviously when comparing these great football players you have to look at the stats in many different ways. The holdback for Reed would be his era but he made up for it with his longevity. Charles Johnson played far fewer seasons but no one would say Reed was better than Megatron. So you have to extrapolate a bit. What if Diggs played 4 more years with Allen? What if Moulds had a better QB?
My only quibble with your post is Rice was in a category all to himself with the second tier being a healthy converstion amongst Reed, Irvin, Brown, Rison, Clark, Monk, Sharpe, Carter, and several others.