Dang, Chris, I was just sitting down to write a post and I noticed that you had already posted. I couldn't help myself. I read it all. And now I don't really have much to say about Don't Be Afraid of the Dark. You covered it all and I think that all three of us are pretty much in agreement about the film.
Some quick notes:
The set-up is way too slow (though this seems common to this sort of horror film).
The creatures are nicely done. Computer or no computer, this is Henson-level creature wizardry. Del Toro's influence is certainly felt here. Contrary to what you wrote, I started wishing that we would see more and more of them. I'd love to see an episode of Jesse and Mike Versus the Tooth Faeries.
Seriously, some of the creaturely activities reminded me of some mischievous moments from the Gremlins films. The movie is at its best when it achieves these Dantean levels of levity.
The myth/back story was just right and the set design/artwork went a long way in helping this film.
This is the most endearing/likeable that Katie Holmes has ever been in any film that I've seen her in.
Maybe it's only because I've also been watching Mildred Pierce, but I can't think of Guy Pearce as anything but a smarmy jerk. I hope that he's a really likeable guy in "real life."
I'm done for now. I'll chime in on any further Dark talk as it happens.