Somewhere along the line the greatest football player ever debate became a debate about which qb has the most rings. It's ridiculous.
There's a reason QBs get MVPs. They are so far and above every other player in terms of importance, it's not even close. They by far have the hardest job. The best player should be the guy who's the best at the hardest job no? JJ Watt was called the best player in football for a while, but it wasn't material to his teams wins or losses.
Anyway, I think the best overall player debate is a weak one. You have to look at best by position in football, given the uneven value of each position. I mean, if you are doing all time drafts to start a team, 10-20 QBs are coming off the board before anybody else.
LT is the best football player I've ever seen. I'm not old enough to have watched him but it sure seems Jim Brown was playing a different game than everyone else.
If that's your style of measuring, then you must be a Wilt Chamberlain guy. Playing a different game.
For running backs, the best I've ever seen was Barry Sanders. He played with like 1 pro bowl lineman in his time. He was other wordly. If you put him on Dallas instead of Emmitt Smith, he might have 30,000 yards lol.