It is telling to me, however, that when Veritas asks him for the truth, after being with soullessSam for a while, Dean has reclassified himself as nothing more than a killer.
I forgot about this. You're right. But I do think that it's attributed more to the nature of hunting- they face so much darkness on a daily basis, I can imagine the lines would blur as to where they stand on the 'monster' scale. It would be fascinating to see the kind of character Dean (and Sam) would be if they had never been exposed to the Supernatural world (though we wouldn't have a show then, and if we did, it'd be boring and generic). Still.

You're welcome! He really is a most astounding character.