I think anything that gives us big exposure in the States is definitely worth doing. I really like the doco idea.
Rather than a movie though, I think it would be better as a TV series, because you could string it out longer. Maybe spend each episode focusing on one aspect of the game (gradually getting more complex) and get the player to talk about it, and how it's different/similar to gridiron. Then the last 5 mins of each episode is a highlights reel of the player utilising each skill.
So for example, the first episode could be based around basic tackling technique. The player could talk about how we don't use pads and helmets, and how every player has to be able to tackle - no offense/defence teams. Then they could show a couple of bloopers about how he totally stuffs it up at first. And then in the last 5 mins, you see him cut down some guys and put some big hits on.