This sounds like a fun idea, and I’m happy to participate (though I would prefer not to be involved in maintaining it).
I think your preferred solution sounds right; though probably it would be better to link to webring.haskell.org/next?from=example.org
rather than relying on the Referrer header (often disabled due to privacy concerns).
Somewhat related is the older http://planet.haskell.org/ which doesn’t look it’s being maintained…