I like the show, but it's far from perfect. I think it's well written for what it is (a large portion of it is a mom/son coming-of-age drama), but I wish they hadn't softened Sarah. Of course, that would be a completely different show -- it'd be more like boot camp all the time.
I also really dig Summer Glau, and Lena Headey is a complete MILF (you have to realize that my taste in women in real life comprises middle-aged women, for the most part. Well, and hermaphrodites.). And having Shirley Manson in the show doesn't hurt. I love TrueBlood, but I already liked the books, so "got it" from the get-go. It's kind of both -- there's definitely fun stuff going on, and they have some very light moments, but then there's all the drama between Sookie and Bill. It's also a nicely ensemblematic (?), which I always enjoy (like Deadwood and Sports Night).