Utilitarianism, self-sacrifice, and that core attachment to people he'd do absolutely anything for, yeah. :)

I think a certain utilitarian mindset would surface in other circumstances as well, and the people-he'd-do-anything-for as well. (Even though it wouldn't turn into feeding someone to a Wraith for them, there's plenty of otherwise not-so-nice things a person could do to help out someone who means a lot to them.) Self-sacrifice is trickier, but I think this may be spot on:

Or just, before you make anyone else do the hard stuff, you do it yourself

I don't know if that's just me, but I think for an introvert it's always easier to rely on yourself than on someone else. (And Sheppard seems almost completely incapable of it in the pilot!)