"to be loved by such a girl", not "to love." I think we're still seeing mainly vanity at work here. But seconding KatharineW's point, he's not a straightforward villain, which is something I really love about Austen's characterizations. I like how one minute you despise him for wanting to "make a small hole" in Fanny's heart, and the next, Austen is pointing out some of his own insecurities when he listens to William's adventures.