I had assumed that the original template (AMI) was of type "template"
and not of type "compute resource".

I think it muddies the definitions to call "templates from which
compute resources can be built" by the name "compute resource". So the
idea would be a template, with only three possible verbs:
- clone (create my own copy of this template, owned by me, and not
necessarily visible to the public)
- instantiate or start (create a compute resource based on this
template, like launching an EC2 instance)
- delete (remove a template, assuming I own it and/or have permission
to delete it)

[BTW, the same verbs are what I envisioned for the noun meaning disk
"snapshot"s.]