I think the nuanced characterizations and the layered situations (the card game at the parsonage is another instance where the action informs on the plot as a whole) are perversely what causes my ultimate deep disappointment in the structure and resolution of the novel.
We shift from seeing the action as it happens, so to speak, to hearing it at second hand in letters. And worse, in wrapping it up, Austen resorts to huge doses of "tell, not show" and I don't always buy it. For example, while I can understand Henry Crawford's seduction of Maria Rushworth out of boredom, spleen and wounded vanity, I don't think he would have gone so far as to run off with her. What care he if she were ruined in her home setting? I would have loved to have seen the seduction and I could have been convinced, but not I didn't see it happen, but was only presented with the fait accompli. The Henry Crawford in my head, while a bounder (because it's rotten to make women love you for the fun of abandoning them), wouldn't have been so stupid.
Similarly, while Julia's elopement with Yates was universally deplored, only to get the bandaid of his having more money and fewer debts than supposed and rendered acceptable, I could only think that Julia had done a smart thing. Once Maria's shame got out, her prospects were ruined.
The epistolary sections seem lazy to me and the end is rushed, almost as if a college student had hit her required number of words and just wanted to end it. I admit I'm playing devil's advocate here to an extent, but in reading it, I knocked a star off my mental rating once I got to the endgame. I think Emma and Persuasion have fewer flaws.
And speaking of Emma, I get a creepy vibe from the Edmund/Fanny relationship, akin to that from the Mr. Knightley/Emma one. A man brings up an impressionable young girl to suit his exacting tastes, and then he marries her. Ugh. I think Mary Crawford (whom I find quite likeable, and far more interesting than Fanny) may have made a lucky escape.