...my reaction is early in the story, JA creates hopes of Mrs Bennet for a marriage between Mr Bingley and a Bennet girl appear as not unfounded i.e the union of a daughter of a local landed gentleman not unimpoverished, with a young man of new gentry status. Further, the Bennet girls are esteemed 'as local beauties' so they may catch his eye. As soon as Jane and Bingley meet at the Meryton Assembly in Ch.3 they are attracted to one another. We have heard of her lovely disposition and sweet temper, which do her credit. Perhaps JA wanted to emphasize hopes of a marriage between them are plausible as Bingley has the fortune and Jane has gentry rank. She will not require a large dowry to marry Mr Bingley.