I wanted to give some thoughts on the revelation about Mac.  I know another thread got into this but angels both of the holy and the fallen variety are kind of my thing (www.youtube.com/c/paranormalencyclopedia) so I might have some additional insights.

First yeah Mac's an angel, particularly one of a type known as the Grigori or the watchers.  In angelology (mostly Jewish) they were given the job of teaching mankind civilization and/or magic (kind of depends on the source) but lusted after human women creating half breed children known as nephillim or anakim (Goliath incidentally was from these blood lines).  Generally they are seen as fallen angels/demons but i don't think that's the case with Mac... at least not exactly.

So in some European folklore there's actually three groups of angels.  The Holy Angels (Michael and the other angels that remain loyal to God), the fallen angels (Satan and his ilk) and what you might call the tripped.  These were angels who refused to take sides when Lucifer rebelled against God.  They weren't cast into Hell but they were no longer allowed to remain in Heaven forcing them out onto the Earth (incidentally Dante mentiones them briefly in The Divine Comedy placing them in the outer part of Limbo, Hell's first level although before Charon and the river Styx).  Some European legends actually associate these angels with the origin of the faeries but I don't think that's where Jim's going. I think Mac is just an angel barred from Heaven but not cast into Hell from the ranks of the Grigori.