Abstraction of NF in ETSI Types, and other questions/ideas

I'd like opinions and answers on the following items:

Has the idea of abstracting NF out of VNF and PNF been considered in the TOSCA node types proposed for ETSI NFV? I think this is of interest to the PNF team and the VES team. See the tosca.nodes.nfv.NF code block and then following discussion for questions.
I know that use of TOSCA semantics was avoided in the SOL001 spec to not require a consumer of the SOL001 spec to need to use TOSCA orchestration. That means to me that SOL001 is a logical data model (LDM) that just happens to use TOSCA vs. an implementation-specific data model. ONAP is an implementation therefore it should be possible for different components to prune and refactor the model to something most useful. If a component or set of components wants to use TOSCA semantics for orchestration those component(s) are thus free to change the model. It means we could change the TOSCA proposed in SOL001 into TOSCA that DOES leverage TOSCA semantics.

tosca.nodes.nfv.NF

# There is no need to derive VNF or PNF node types at the *data model* level
# Use composition to cover the differences
  tosca.nodes.nfv.NF:
    derived_from: tosca.nodes.Root
    properties:
      descriptor_id: 
        type: string # GUID
        required: true
      descriptor_version: 
        type: string
        required: true
      provider: 
        type: string
        required: true
      product_name: 
        type: string
        required: true
      software_version: 
        type: string
        required: true
      product_info_name: 
        type: string
        required: false
      product_info_description: 
        type: string
        required: false
      localization_languages:
        type: list
        entry_schema:
          type: string
        required: false
      default_localization_language:
        type: string
        required: false
      # configurable_properties:  
        # type: tosca.datatypes.nfv.VnfConfigurableProperties <== remove Vnf prefix?
        # required: true
      # modifiable_attributes:  
        # type: tosca.datatypes.nfv.VnfInfoModifiableAttributes <== remove Vnf prefix?
        # required: true    
      # lcm_operations_configuration: # what use is made of this and by whom?
        # type: tosca.datatypes.nfv.NfLcmOperationsConfiguration
        # description: Describes the configuration parameters for the NF LCM operations
        # required: true        
     # monitoring_parameters:
       # type: list
       # entry_schema:
       #   type: tosca.datatypes.nfv.NfMonitoringParameter
       # description: Describes monitoring parameters applicable to the NF.
       # required: false
      flavour_id:
        type: string
        required: true
      # flavour_description:  # should be in the NF's DF definition and not need to be provided here (join it with the id)
        # type: string
        # required: false   
      # vnfm_info:    # I wouldn't recommend putting this in any static model. Maybe a reference to a dynamic property?
        # type: list
        # entry_schema:
          # type: string
        # required: true  
    #capabilities:
      # monitoring_parameter:
        # modelled as ad hoc capabilities in the VNF node template
    requirements:
      - virtual_link:
          capability: tosca.capabilities.nfv.VirtualLinkable
          relationship: tosca.relationships.nfv.VirtualLinksTo
          node: tosca.nodes.nfv.VirtualLink   # Change to remove vnf
          occurrences: [ 0, UNBOUNDED ]
        
# Work with OASIS on normative representations of compute, storage, architecture, etc.  
# I'll just lump them into ExecutionEnvironmentAspects for this example  
  
  tosca.capabilities.nfv.Moveable:
    derived_from: tosca.capabilities.Root  
  
  # Only PNFs could have this capability     
  tosca.capabilities.nfv.PhysicallyMoveable:
    derived_from: tosca.capabilities.nfv.Moveable
    
  # Only VNFs could have this capability     
  tosca.capabilities.nfv.VirtuallyMoveable:
    derived_from: tosca.capabilities.nfv.Moveable
 
  # Only PNFs could have this capability
  tosca.capabilities.nfv.PurposeBuiltHostingPlatform:
    derived_from: tosca.capabilities.Root
    properties:
      provider:
        type: string
        required: true
      serial_number:
        type: string
        required: false
    attributes:
      serial_number:
        type: string
        required: true
    valid_source_types: []

PNF

  VendorABC.capabilities.CanHostVendorABCRouter:
    derived_from: tosca.capabilities.nfv.PurposeBuiltHostingPlatform
    valid_source_types: [VendorABC.nodes.MyPhysicalRouter]
    
  VendorABC.nodes.MyPhysicalRouter:   # similar to BaseStation
    derived_from:  tosca.nodes.nfv.NF
    properties:
      # omitted for brevity
    capabilities: 
      forwarding:  # similar to over the air RF service
        type: onap.capabilities.PacketForwarding
    requirements:
    - host: AssociatedHardware
         
  # This IS the physical aspect of the device, my NF can't work without this      
  AssociatedHardware:   # similar to the airscale box the base station runs on
    derived_from: tosca.nodes.Root
    properties:
      geographic_location_id:
        type: string
    capabilities:
      moveable:
        type: tosca.capabilities.nfv.PhysicallyMoveable
      host:
        type: tosca.capabilities.ExecutionEnvironmentAspects
      specificHardware:
        type: VendorABC.capabilities.CanHostVendorABCRouter
        properties:
          serial_number: someValue

VNF

  VendorXYZ.nodes.MyVirtualRouter:
    derived_from:  tosca.nodes.nfv.NF
    description: this node will be the type of a substitution mapping for a topology template containing the VNFCs for this VNF and their dependencies on their execution environments
    properties:
      # omitted for brevity
    capabilities: 
      forwarding:  # similar to over the air RF service
        type: onap.capabilities.PacketForwarding

Service that needs Router

I need to understand what all the subtyping and indirection is doing in the "modifiable properties example" code block. There is a data type defined which extends VnfInfoModifiableAttributes. It defines its own derived datatype for the extensions property that introduces the http_proxy and https_proxy properties. If I had simply put http_proxy and https_proxy as properties on my derived VNF, I would have had equal access to them in the script; I would have referenced them in a shorter way (i.e., \[vnf, http_proxy\]). I am missing the beauty of all the indirection. Can someone help?