This is a tough one. Win a Natty, what would that offset? For example, would 1 Natty & 2 poor season plus 2 good seasons be better than 2 extremely good, 3 very good, 4 mediocre and 2 bad ones? I think so. Similarly, beating the mutts 3IAR how much would that offset? Chan's no losing seasons is an accomplishment, but there were not any 10+ win seasons. Ross had the Natty & 2 good seasons out of 5. It stands to reason he might have another great season in him in 5 years and at least or 2 good ones.
I think Johnson had one of 3 great runs since Dodd. Hard to beat the Natty, same goes for 3IAR. Worst case he had the 3rd best run in 50 years and that's nothing to sneeze at. I think he has a good solid argument for 2nd place, not so sure he has a great argument for #1.