Dr Michael Heiser is big on this stuff as well. He wrote a “novel” called Unseen Realm about the divine council, etc.
He’s all over the watchers, 1 Enoch and how it explains Genesis 6:1-4.
Meanwhile, still reading your OP...
Have read all (I think) of Heiser’s books. He does good work.
Have you read Gary Wayne’s book “The Genesis 6 Conspiracy?”