I would rather see a separate blockchain feature for rewarding account referrers and registrars, as was briefly discussed here. I don't like the idea of a user easily getting around paying the cut to their referrer/registrar by switching clients. The registrar is more likely to pay the account registration fee for a new user if they know they will continue getting a cut of author/curator rewards (up until the accumulated pay to the referrer/registrar reaches some limit) regardless of what client that user ends up using.