One of the things I did not really get in Mansfield Park was what the big deal was about putting on the play. Sure, Sir Thomas would be annoyed to find his library and billiards room had been turned into a stage and green room, but Edmund's and Fanny's reservations about the play go further than that. Lady Bertram, Mrs Norris, Mrs Grant and Dr Grant don't seem to have a problem with it. Lovers' Vows does not seem like a very scandalous play. Edmund and Fanny's sense of propriety just seems incredible. I wonder whether Jane Austen was just being too subtle for me, or that the 200 year time gap was too hard to bridge.
One interesting point about it was that although Fanny resists being drawn into it, her resistance is finally overcome. That makes it more uncertain that Fanny will resist Henry Crawford's attentions later on.