There is no conformance statement to define the API capability. Which operations are available on which resources? Similarly, no description of the interactions within which these resources are used which limits ability to evaluate them. Hopefully this is being addressed in the forthcoming release.
In models, have the undocumented properties been constrained out (i.e. cardinality 0…0)? What about properties of base classes e.g. DomainResource, Resource
For resource reference resources it can be useful to provide *.display but not *.reference as this gives natural bound to data that can be retrieved by computational exploration.
The profiles may be useful elsewhere. Is the GPConnect-* naming convention going to act as a barrier to reuse?