You show up some of their family differences nicely, but Author Austen spends entire novels on people who are very different, and have very different family backgrounds, finding happiness together, so I do not think that there is a broader application to be found in such a similar shared history.

In the case of Mrs. Dashwood's family, compared to Mrs. Ferrar's family, their similar distancing of one member is so overshadowed for me by the differences in their actual morality, and the constant affection of one versus the imperfect feelings of the other, that I never noticed the parallel until you brought it up.

I like, however, that Edward's and Elinor's principles are so steady and they are so similar in that respect, that they approve of each others' choices, even when it injures their own chances. Edward certainly never learned that from his controlling and self-centered mother. Elinor may have not gotten her self-control or practicality from her mother, but it is obvious that they hold the same high standards of principles. Mrs. Dashwood is sometimes selfish in her behavior, but she never wants her children to suffer, does not want to control their lives, and would really sacrifice anything for any of them.