It would be a sort of "intermediary" relay that aggregates from others and drop retarded "pura vida" messages. And yeah, like the other commentor said, clients would have to just use that one relay and no others, which is a dealbreaker for most. It isn't really in the spirit of Nostr to filter things at the relay level.
I could see using it as a personal relay for my use only, though (or anyone else who wants to run their own). Will need to hash out the idea some more.