"Tradenames are not protectable if they are not also trademarks." Not correct, it is just that the protection is greater if they are also used as trademarks or servicemarks. Also, "first to use is more important than first to register" is self-contradictory because use is required to get a registration. I think you meant first to to use is more important than first to APPLY to register. Even that is sometimes not correct if earlier application is followed up by timely registration.