hackuser posted a requirement which has my full support:
Since you're doing machine learning, try and apply that to avoid showing me articles with overlapping content. Often quite a few sites I follow will cover the same thing, and obviously, I want to read it only once.
To clarify my version of the idea, I would like to see all the articles on the same subject but grouped together, perhaps in a collapsible outline, so I can choose which one or more articles I want to read on the subject.