We're about to start work on this. Do you think people would make the effort of essentially jumping through a hoop in order to hear new music that was sent to them?

This is awesome feedback. A couple of points.

We already have “lock songbox to an email address” as a security feature. This works by allowing you - the content owner - to set an email address of your intended recipient. When the songbox is opened a PIN code which is required for access is sent to that email address.

That being said, your idea is still valid as it works in a subtly different way.

We’ll add it to the roadmap.