@robert.down I left some comments inline. It looks really good and I am excited about the direction we are going 
Focusing documents on specific audiences is a great idea so that users can know that they are reading the right level of documentation for their task.
According to NNGroup:
Even though it is better if the system can be used without documentation, it may be necessary to provide help and documentation. Any such information should be easy to search, focused on the user’s task, list concrete steps to be carried out, and not be too large.
See: 10 Usability Heuristics for User Interface Design
The way you broke up documents into How-to, Guides and Reference seems to accomplish this goal. In the future, i hope that we can provide this documentation as a part of the user’s workflow. Similar to what intercom is trying to do with their knowledge base integration:
https://marketing.intercomassets.com/assets/messenger/videos/self-service-953d4ba9add4dd76988540ada283820daae78a078b832f061f6633f1f9f479c3.mp4#t=1