My take on the problem of filtering crap while still allowing the unexpected useful content to come through is filtering out everything unwanted.

Back in the Usenet days I solve the same problem with liberal use of filters in nn. I could filter out any thread with disruptive participants, or using keywords against titles/post content. Other than the horrible UX for defining the filters it was actually working quite well.

I wish there was more RSS readers with advanced filtering capabilities. I haven't tried Feedly's mute filters feature yet. On paper it looks like exactly what I'd need.