This all looks good, except for the "dc:creator" property...any reason we're not using the Web Annotation native "creator" property instead? We could do it as such:
"creator": {
"name": "Getty Guide",
},
With the ability to use some of the other properties (like ID) down the line when we need to.
This is a good question. My thought was that the Web Annotations model identified the creator as a Relationship resource while dcterms:creator allowed a simple literal. Since the ID Manager isn't actually RDF, we could just make it a string that is a literal for now and then replace it with a URI in the future if that's where we wanted to go.