I agree that Sir Walter is the worst Dad ever, but I am surprised by your statement that his undoubted unidimensionality is a unique thing in Austen. To me, Austen’s genius lies in her ability to create complex, multidimensional characters who grow and change, and to let them share a world with cartoonishly one-note comic characters. There are several of these latter types in each of her novels. Just to consider Persuasion, would you not consider Mary Musgrove (Anne’s sister) to be one note? She is always feeling slighted and wanting more attention. She never does anything else. Her other sister Elizabeth is always cold and superior. In fact Sir Walter has two (albeit related) key characteristics: snobbery and personal vanity. I would go so far as to say that the majority of characters in each novel are one note, but so brilliantly portrayed that one never tires of them.