It does seem that our JA is wielding her wit in double-edged satire. She not only blasts the criticism of novels generally (and, especially, gothic novels and the like), but, more subtly, she jabs at gothic novels themselves. The contradistinction between Isabella and Catherine as heroines sets up an experiment of sorts. As Carol notes, are the qualities exalted in the heroine ones that necessarily lead to virtue, et cetera?

Emmeline raises a great point too—how much is Isabella's attitude consciously assumed, as opposed to intrinsic? We learn very early on that she is awash in the gothic novel experience. How much, if at all, has this amplified the effect of her disposition and life circumstances? Has she identified with the heroine role so much as to overtly seek to emulate her, if not actually, then in appearances? If so, what will her story imply about the impact of gothic novels?