Ah, I see now about Archangel and such. I imagine Zadkiel was a Seraph, then, if he was involved in the work with the Demonic Parasite, though feel free to say otherwise imagine you prefer. As far as sort of moderate proficiency in most abilities that's fine--I figure there are a few he probably mastered, such as the Tamer aspect and some degrees of Weather for personal reasons (he really likes rain), but there are plenty of others he would only have trained for posterity.

And correct, he has never died. He prefers not to engage in violence personally at the best of times and he's powerful enough to handle himself on the rare occasions he has to.