I have also thought about things like that. I'm currently working on a mainstream-focused RSS reader that comes with a large feed catalog and a feed-spider mechanism: when a site like Hacker News posts a link to a yet-unknown site, it automatically searches the website for an RSS feed, and if it finds one, it automatically adds it.

While my main project is the RSS reader itself, I think the ever-growing feed catalog is something that would be interesting as a stand-alone project: a reader-neutral catalog of RSS feeds.

An interesting observation is how people are currently discovering podcasts vs how they discover news feeds. Most podcasts are found on podcast directories, usually embedded in the podcast listener's platform. While discovering an RSS feed is more like i-found-an-interesting-site-does-it-have-an-rss-feed, which works ok for enthusiasts, but is far too complicated for mainstream users.

From a publisher's perspective, the main issue with RSS feeds is that if they contain the full text instead of a summary, they are currently hard to monetize. And a summary-only feed is just not that great.

A solution may be a YouTube-like model, where feed readers either insert ads or charge their users monthly fees that are redistributed to feeds.