I saw Whit Stillman's movie Love and Friendship a few months ago. It's an excellent adaptation of Austen's novella Lady Susan (with a title stolen, inexplicably, from another of her juvenile works) that understand the black humor at the heart of her fiction. But it helps that Lady Susan bares that black humor like none of Austen's other novels; the title character is, unlike the various prigs and snobs that people her major works, unapologetically nasty.
Part of that may be due to Austen's choice to write the novella in the epistolary form, as a series of letters. There's no social code of conversation that restrains her letters to her friend Mrs. Johnson, wherein she describes just how much she hates her daughter, and her manipulative glee in forcing the brother of her late husband's brother's wife (I know) to fall in love with her. She does it just for the pleasure of it; she's really in love with a man named Manwaring--you can tell by his name how much masculinity he exudes--whose current wife kicked Susan out of their house for carrying on an affair under her nose.
Susan wants her "stupid" daughter Frederica to marry the loathsome Sir James Martin:
Upon the whole, I commend my own conduct in this affair extremely, and regard it as a very happy instance of circumspection and tenderness. Some mothers would have insisted on their daughter's accepting so good an offer on the first overture, but I could not answer it to myself to force Frederica into a marriage from which her heart revolted; and instead of adopting so harsh a measure, merely propose to make it her own choice, by rendering her thoroughly uncomfortable till she does accept him. But enough of this tiresome girl.
The fun of Lady Susan stems from the way in which we get to see the characters in their private confidences. We are so used to "reading between the lines" to see the vanities and malices at work in her novels, but here we get to see those interior motives at their fullest expression. It would have been nice for a character as terrific as Lady Susan to have a more substantial novel in which to work her schemes, which, while nefarious, fail quickly and spectacularly. Stillman's film does a good job of filling out the narrative to accomplish that--especially by beefing up comic actor Tom Bennett's role as Sir James. You should see the movie--but if you're strapped for time, the novella is probably quicker!