Yeah, the Guardians and the Axe. If you wanted them in the show, they should have been foreshadowed back in the Shadow men episode. Or Buffy could have had a dream about them at some point. So much of Season 7 is filler, and then an entire season worth of lore gets dropped in each of the last five episodes.
Re: Watchers: The series basically wants to exploit your knowledge of Merlin, the half-demon wizard who trained King Arthur in the virtues of being a good king. I would argue, you are supposed to assume that they have a moral purpose, like any parent, of providing an indoctrination, upbringing and security during the formative years, and then slowly backing away the child reaches maturity, but with conflict that defines us as individuals. This is complicated by two things 1. Joss's parents basically abandoned him as a teenager, so he sees any parental involvement after age 13 as sinister and 2. We never directly see the Council do anything useful or even moral.
Re: Race: Okay, here's the thing. Black hair is a very sensitive topic, now more than it was 20 years ago. But white people don't understand that. So, Buffy or Joss was making a joke about a topic he couldn't understand the full implications of. He probably thought it was more like showing up to an job with an unpressed shirt. However, I could see a Black teenage girl of the type Buffy would have hung out with in LA, that is, played by Stacy Dash and with the personality of Cordelia, bully another Black Girl (Black Willow?) by telling her that her hair was un-presentable. Because that is how black girls bully each other. And Buffy just picked up on it. I don't think it means Joss is a racist, or Buffy is one, just that they were using a taunt that would have been unremarkable if said by an American person with west African hair, but hateful if said by a person with European or Asiatic hair. Because I want to stress, this is about hair texture, not skin color.