My goal is to learn what options there are.
When I first saw this diagram...
https://openvpn.net/vpn-server-resources/site-to-site-routing-explained-in-detail/
...I thought "Great, they are going to show the various ways you can run OpenVPN" but alas there's only one diagram.
The problem is that I know I will have to answer questions from my colleagues like "What does this mean" and I want to know how to reply.