As a writer, one of the things a character in one of my stories stated took me aback. when writing, sometimes a sort of 'other body muse takes over the keyboard. The statement was: "God does miracles, angels use technology. And there are good angels and bad angels using technologies, in dimensions of space and time we cannot now sense."
I am leaning to the notion that the 'aliens' are angels, fallen and otherwise, since they are seen in the first Heaven, which is the atmosphere and beyond. The second Heaven is not dimensionally / spacetime coordinate system open to our reality. Near death experiences and remote viewing may be the best clues we have regarding this different real coordinate system.
I have read all Dr John Mack's accounts of abductee experiences and there is genetic hybridization work going on in all of them.
As an aside, I write short stories also and can vouch for your experience of having characters say and do things that come from somewhere outside the writer's mind and consciousness. Strange, huh.;-) There is something rather supernatural about it, isn't there?