Also most playoff road wins. None of your other flashy QB's can attest to that. And as I said before, to beat what some consider the greatest to play the game in Brady. Twice. On the biggest stage.
If the average fan in the future sees that, they'd be hard pressed to say Eli wasn't one the of best QB's to play the position.
Road playoff wins is another great achievement but couldn't that be argued to be more of a team accomplishment and perhaps more of a sign of the success Coughlin has on the road in the playoffs?
Eli beating Brady is a tough one. Some people will see it that way but others see the two QBs just playing different defenses. Brady certainly put the Patriots in good enough spots to beat the Giants in both SBs but his defense couldn't hold. It's very debatable.
I'm with Harooni (lol) that Eli could use a regular season MVP to really cement his place in the HoF today. That's just me though.
You have your stats guys (Marino, Peyton, etc ...), your "legendary moment" guys (Elway, Eli) and multiple ring guys (Bradshaw, Montana, Brady, etc ...).
If you look at it like that, you can actually make a strong case for Elway being the best QB in football history, since he's managed to be in all three groups.