We have a good mix of benevolent and malevolent spirits. When Bo (Bolander) and I originally came up with the idea, it was because we'd both grown up in pretty spooky areas. Also, the Clark Ashton Smith and Shirley Jackson stories, two of the most iconic genius loci stories in spec fic, were pretty creepy.
So when I did the call, I asked for both. Steve Long, Ken Liu, K.C. Norton, and a bunch of others have benevolent spirits, while Mercedes Yardley, Seanan McGuire, and Damien Angelica Walters have...not benevolent spirits. :P I'd say we have about a 50/50.
But the other thing is that nature is seldom strictly benevolent, so when I was choosing the stories, I looked for that nuance, where the spirits weren't quite black and white, and weren't quite human. I think we succeeded pretty well.