Heh, not sure if they want to bring up those guys anymore because we should have heard about them by now. I think that ship has sailed.

Well.... Supernatural is sort of right, but mostly wrong in the Bible stuff...

The angels that joined Lucifer to disobey God are known as demons.
In Supernatural, demons are humans who've been twisted in Hell.
In Supernatural most if not all the angels disobeyed God in their own ways.
In Supernatural God isn't even really worthy of obedience.

In the Bible, angels don't need vessels to speak with humans. (Although Supernatural does have a point that it is true demons possess people... and if demons are angels gone bad, then angels possessing people isn't that far off.) I think possession of either kind good or bad is a violation of human free will or something so real angels don't.

I get that they make humans into demons in hell as a way for Dean to fear what he would one day become, but I kind of wish it was actual demons (evil angels) vs angels.

In the SPN anime azazel had a line actually claiming he was a falling angel. I think it would be interesting to have a difference between some of the lesser and human converted ones.

One of the SPN companions (S4 i think) one of the writers - Edlund IIRC - said they had this idea that Lucifer used a bit of his essence to create demons so demons in the show are a strange mix of ghosts and angels. I used to like that idea (before the angel lore got really fragged) as it kind of made some sense that ghostly possession had some features which angelic possession didn't and demonic had a blend of the two.

i.e. Ghosts couldn't possess dead bodies but didn't need permission. Angels could rez dead bodies and then ask for permission. So demons had the ability to take over living or dead and without permission and even keep a dead body going for awhile (but couldn't heal it). Anyway, once upon a time I put a whole lot more thought and work into it before S9 just screwed up everything.