Firstly, the gossipy side of Buffy is part of the show being ironic and to be fair chances are that a teenager would be more of a gossip than a 30 something woman. I would say that for the first three seasons of the show that Buffy as a character has a big interst in guys, but again that is a naive teenage thing which she grows out of around about mid-season 4, and the show is meant to be about growing up after. I never get the impression that Buffy's complete focus is romance or than that defines her. And like I said don't forget the other female characters on the show. Is Faith a typical girlie character? Is Willow a typical Girlie character? Is Cordy a typical girlie character? etc..
No, Buffy isn't, because she doesn't act macho, yes she's attractive, but the show doesn't throw that in your face like those other shows. Again what about the other characters?