I'm using a heavily customized 2005-era fork of tt-rss.

Early on in my use I recognized some feeds I wanted to read end-to-end (often individual blogs). Others (Hackaday, other aggregators) I dip into periodically. To keep the UI uncluttered I use naming of the feeds to differentiate. I could easily see adding some schema and UI to handle segregating the feeds, too.

I've thought about adding an algorithmic feed driven from the various feeds I only dip into.

I had some discussion on here re: feed readers that might publish a feed of "starred / tagged" articles. I would love to drive my algorithmic feed from a recommendation system based in part on the subscribing to these "starred" articles from the authors of feeds I already read. A decentralized system that drove recommendations like this would be awesome to play with.