I am re-reading Jane Austen's novels in order of publication and having read Mansfield Park I have recently started on Emma. I studied the book for A level in the late 1960s and apart from listening to an Audio version of it I haven't re-read it since. The book has a lighter feel to it that Mansfield Park but it is still a very moral book in some ways. Emma is frequently reproved by Mr Knightley for not treating people how she should do - most notably being rude to Miss Bates in the famous Box Hill incident. Emma does learn throughout the book and becomes a better person in the long run.
Many people like Frank Churchill as a character but I find him too smarmy and insincere. He does not treat Jane Fairfax well at all especially when you consider his clandestine relationship with her. It is a book which repays several readings as do all Jane Austen's novels.