Matt, absolutely! It would be so appropriate. That's one of the reasons why the usual angel in fiction or movies bugs me so much: in the Bible, the appearance of an angel to a human was always followed by the angel saying, "Fear not!" To me, this says that angels are not cute little babies or lovely young ladies. An angel's appearance should not make someone say, "Awww, isn't s/he cute??" I have a great illustration I cut out of a Focus on the Family article once that shows a group of angels armed with swords and looking like fierce warriors. Still not as scary as a real appearance would be, I'm sure, but way more like what I imagine an angel looks like.
And skylar, what a good point to make about aliens - the definition of alien means "totally foreign to", "completely different than", so you're right - angels are aliens. And I'll bet they're way scarier (in a totally "other" sense) than ET or the aliens from Star Trek or so on could ever be, since all of those aliens are products of human imagination, and angels are products of God's imagination, so much wider and bigger and "other" than we can ever get our brain wrapped around.
All writers should praise Him, as the source of all inspiration and creative ability. Just think, each time we create a character or paint a scene or have a baby or do anything else that creates something (or someone), we are expressing that aspect of the Eternal Father. Isn't that a cool thought?