In the Categories proposal, when the carrier (etc.) is asserted as a resource, additional assertions are made about that resource. This is shown in example 1, where we see:
rdfs:label “audio disc”
This is an excellent opportunity to simplify by incorporating this type of assertion into the carrier, content, media and genre schemes themselves, in particular since they are maintained by LC. This would spare libraries the work of making such assertions for each Instance, and reduce the clutter of identical assertions on a lot of different servers.