what does he have to offer to the HA? He is without fear and THRIVES on adrenaline and excitement. while he's not the easiest person to get along with, if he's convinced to do something, he WILL do it, planet-eating super creeps in the way or not and he will have damn fun doing it! He may join because they may need him for something, i think.also, being the more semi-devious, he'll be albe to think like a villain and how to be invasive among them.
since he's a very independant character, i think he will need to be invited rather than join willingly because he wouldnt go out've his way to join an organization with rules to bog him down and what not. BUT, if they have something to offer him or to keep his interests he will cooperate and make sure he does what he's needed to do.
as for his relationship with the other characters. i imagine he could be abrasive, at least at first, but if there are some that accept his flaws he will naturally be more willing to get along with those individuals better. the chicks i imagine he'll hit on some, and Desperado and he will engage in some harsh drinking contests im sure since HE thinks he's the greatest drinker that's ever lived.
so much for a few sentances i guess, really sorry, just wanted to get my full thought out there!
so here he is (but ussually without the partches):

and the link to the comic is in my sig.