Oh, so it is like Delegated PoW service. Any suspicious users can be redirected to your service to do PoW to make them whitelisted on certain relays?
Same, we can probably see it in near future. Especially when adoption of new users increase rapidly. Honestly, client with gossip model discovery like https://github.com/mikedilger/gossip + fully implementarion of NIP-65 will alleviate some burden of relays