As to your last Henry surprise, the visit to Portsmouth- this particular one gets me every time.

The end of ch. 42
The wonderful improvement which she still fancied in Mr. Crawford was the nearest to administering comfort of anything within the current of her thoughts. Not considering in how different a circle she had been just seeing him, nor how much might be owing to contrast, she was quite persuaded of his being astonishingly more gentle and regardful of others than formerly. And, if in little things, must it not be so in great? So anxious for her health and comfort, so very feeling as he now expressed himself, and really seemed,

One thinks with that buildup that perhaps Sir Thomas' scheme is working and that she's perhaps beginning to contemplate a marriage to him. But then her thoughts finish.
.... might not it be fairly supposed that he would not much longer persevere in a suit so distressing to her?

I don't know why but it makes me laugh every time.

I wonder what others think of the difference in Henry's behavior from when Fanny last saw him, when he was grilling her in such an ungentlemanly way to the Portsmouth visit. He behaved much better. I wondered if this was merely adapting to Fanny's tastes or whether seeing the lower circumstances of Fanny's life in Portsmouth and her father's more ungentlemanly behavior shook him into a better sense of propriety- for example being unwilling to leave the women on their walk about Portsmouth.

The surprise for me on this reading is Edmund, even though he's been lumping Fanny and Mary together as equally wonderful all along, he was praising Fanny so highly that it seems natural that after the Mary debacle, he in time transfers his romantic affections to Fanny.

ch. 48
Having once set out, and felt that he had done so on this road to happiness, there was nothing on the side of prudence to stop him or make his progress slow; no doubts of her deserving, no fears of opposition of taste, no need of drawing new hopes of happiness from dissimilarity of temper. Her mind, disposition, opinions, and habits wanted no half–concealment, no self–deception on the present, no reliance on future improvement. Even in the midst of his late infatuation, he had acknowledged Fanny’s mental superiority. What must be his sense of it now, therefore? She was of course only too good for him; but as nobody minds having what is too good for them,...