I guess thats were we differ. I always thought the charm of Coulson was that he was this seemly normal guy but actually had more to offer than what his demeanor portrays. And because of that he is like one of the fans since every person in the world has at one time been underestimated and completely counted out.
Besides there are no average S.H.E.I.L.D agents. I pretty sure it's written in their hand book somewhere "Those who can not kick a little A&* Need not apply." If not I'm sure Samuel Jackson will add it in.