I don't think there will be a way to differentiate between a traditional RC plane and a drone. Both use a transmitter and receiver, and both can be equipped with a camera. And they can have the same range. A quad would be safer in that usually, they have software that will cause them to land if they lose contact with the transmitter. That is not the case with a traditional RC plane. So one is not necessarily safer than the other. For those who feel the government can't register all the kit-built models. You are right. However, the government CAN require the registration of ANY new receiver, and even go as far as requiring a background check just as if it were a firearm. The ATF does the same with guns. You can buy a new trigger assembly for a Ruger 10/22, a new barrel, or any other part you want. But the lower receiver is the serial-numbered part, which cannot be transferred by a gun dealer without a background check and the proper paper work. Registration of the receiver on a model plane would cause that to be the serial-numbered part, thus assigning that serial number to which ever model aircraft the receiver goes into.
Don't discount the long arm of the U.S. government. It has a long reach!