]For another, JA uses her dialog to relate a lot of relevant detail,

I agree wholeheartedly here. Miss Bates is often overlooked as simply an overtalkative spinster but embedded in her non-stop talk one can glean some wonderful information if you're paying close attention. I recently read that Miss Bates's speech is one of the triumphs of the book and refers to her speech as lucid muddle. Definitely a good deal of amusement associated with her. I think it is very clever the way JA uses her to impart news and portray the diversity of villiage life.