Still, I think I've finally managed to get the paint scheme for the army down; I've been through 10+ testers, and not really being satisfied with any of them. However, I saw this pic online:
... And it inspired me. It has the cold, otherworldly feel of something utterly wrong, and being light enough to "pop out" on the tabletop, while still feeling dark.
I won't go so far as to say that I've nailed it, but I think my version looks pretty good, is not to difficult/time consuming to paint, and has some of the feel of the image: