wayspooled, I liked the Windrose books a lot, but not the Darwath books so much. The Benjamin January books might be better than either, even if I do generally prefer sf/fantasy (though I read a fair amount of historical fiction as well). One thing that is nice is that I think the later books are as good as the earlier ones, particularly the last one (Dead Water).
If you liked the Windrose books, you'd probably like Stranger At The Wedding, which is set in the same universe, though none of the characters overlap. It's a standalone, with more of a mystery feel, and quite funny in many places, though the overall story is serious.
Unfortunately I can't recommend Sisters of the Raven or Circle of the Moon. They were ok, and I'm not sorry I read them, but they kind of dragged along in places. They just weren't as tightly plotted as the Windrose books or the Benjamin January books.