It would be nice to have an "auto-expire posts after X days" feature for specific feeds.
I read MANY feeds, and there are some that I consider "news" feeds and others that are more like "blogs and magazines". News get old after a few days, but I still want to read the blogs.
However what I see is that those News feeds publish a lot of content, flooding my feedly while the stuff that I consider more important gets drowned and hidden. After some time I get a feedly with 10000+ entries and feel overwhelmed, so I stop using it altogether.
It would help a lot if I could just say that posts from "News" sites only appear for 3 days. After that I have either seen the news item somewhere - or I just don't care anymore. But most importantly: It would keep feedly down to a size that I still can manage.
I know there is a "Mark As Read...Older Than One Day" menu item, but I have to do that manually - and I haven't found it on Android, yet. Being able to do that automatically would be a blessing.