I've been using Newsblur for a while. It's kind of weird as RSS readers ago, but it does have one signature trick, which is that it has some content filtering options. For example, you can, like, downvote arbitrary text strings in post titles, as well as tags and authors. This is great if you, for example, hate one particular intellectual property that every nerd on the internet loves. It doesn't work as well as keyword muting on most platforms that support it, but a lot of feed readers don't have anything like it.
Unfortunately the latter fields aren't that useful in RSS these days, as I think there are fewer multi-author blogs/publications that are interesting, and it's less and less common for places to actually include tagging in feeds.
That being said, I declared RSS bankruptcy years ago and have not attempted to remedy that apart from a couple of blogs. So, it'll be a while before I'm ready to make RSS a central part of how I follow folks again.
As mentioned above, one of the things I like about it is that you can filter out tags and phrases from your feeds, but there's another feature that I've never really used in the past, but maybe I would actually find a use case for in my post-Cohost era of RSS consumption.
It has a built in link-reblogging function where you can share any item in your feeds in a quick and light way that feels much like rechosting. The thing you're sharing is the main feature, and you're just adding a little comment or nothing at all, so it doesn't create a feeling that you have to say something meaty about the thing you're sharing. And since it's baked into newsblur itself, you just hit shift-s to share a thing.
I imagine some other RSS readers probably have similar functionality and there are definitely standalone linkblogging solutions, but since I already have this maybe I should start using it.
And it has its own feed as well of course that others could subscribe to or which you could feed into something else. (This again has me wanting a solution for combining multiple feeds into one.. Ruby mentioned rss.app as one option, but it does cost money and perhaps a bit more than I would want to spend for this specific thing.)