Okay, I have thrown something together. Please fix it as needed, or ask me to start over, or whatever.
I created four new forums in a new category, "Dummy Forums," just to show how the various usergroups work with each forum type.
I created four basic usergroups.
Then I put a thread in Tutorials explaining what it all means.
This is the most sustained intellectual effort I have made in a couple of weeks.* Meaning, look out. Fix what needs fixing!
*I spent this morning watching Independence Day. I also read half a Hornblower book.