Suppose there is a relay that only accepts PoW notes, another that only accepts notes from your WoT, another that only accepts notes once they got enough zaps or likes, another that is manually curated by a group of people, another that only takes notes from people that pay to publish, another that only takes notes classified as talking about some given subject.

Then we could have a client mode that fetches from all these, then only displays notes that have showed up in at least 2, or 3, of these -- or whatever combination.