It's true she's not much of a people person, but I kinda like her in her own way. She's very polished and "break the glass ceiling" in how she goes about things and doesn't get flustered by anything. It takes a cool head to run Torchwood and few do that better than her.
I think part of her dislike for Jack stems from that fact that he doesn't fit into her neat little hierarchy. Torchwood One probably could have done a lot of good things with their research and we know all too well that it only takes one little piece of technology to go haywire for it to sending everything crumbling (Cardiff have experienced that more than once).