There are a few things that can help readers pick the stories they/we want to read and those we don't. First, in the "for you" feed and the topic feeds, I routinely see the same articles repeat themselves as I scroll down, which is irritating. Second, I wish there was a way to tell the app to not continue showing an article. That way, I can swipe away things that don't interest me, and retain those that do. Finally, you said "Authors who promote their article through social media, through email, to their followers, and on publications are now more likely to get their article picked up for a boost." That's likely to cause a problem imho, because it allows for off-platform gaming which you'll have a much harder time policing, and lets people who have large followings elsewhere to drown out those who don't.