Can turning static text into something more like a shared canvas fuel more active participation among readers? A shared surface you can mark up can help the author understand what resonates with readers, and help readers who prefer to skim find what matters quickly.
You can highlight text in posts on our website, and highlights are now distinctive — color and line quality are different for each person who marks up a page. I think distinctive marks may help people intuit that highlights are not made by one person (i.e., the author) but are instead contributions from readers.