Thinking more about your post, Louisa and Captain Wentworth walking together does seem to hint again at what Anne noticed the day before about the contrast between naval manners and her own father and sister's formality (from chapter 11, Anne thinks that the Harvilles show such a bewitching charm in a degree of hospitality so uncommon, so unlike the usual style of give-and-take invitations, and dinners of formality and display).

And here Captain Wentworth is in a relaxed way going for a stroll before breakfast. And it shows a similarity between Anne and the Miss Musgroves, that all of them are up early in the morning, engaging in the world, so we can see how CW can be attracted both to the Miss Musgroves and to Anne.