To be honest, would I rather live in San Diego or Seattle? Sure. I've been to both, loved them, and could see myself really enjoying them. I haven't been to Portland, but I'm guessing I'd probably dig it, too.
That said, I am able to afford a certain type of lifestyle living in KC that I couldn't have if I lived in any of those other places, plus, I'm around lifelong friends, family, and other things that I care about (i.e. KSU).
If I were to give an aggregate score on all facets of my life (everything Pete said), KC probably wins, therefore, I stay.