This is a marvelous send-up of the New York theater world. It is not an adaptation of an Jane Austen work and is not a period drama. I think many reviewers have been disappointed that the brief 18th century scenes are not good writing, or good acting. The director doesn't intend for them to be examples of good film-making, they are examples of self-indulgent theater illustrating the personalities of the main characters.
Nevertheless, it is wonderfully entertaining.