Quick Docs are mostly for all generic use cases a user would like to use Fedora for like booting and installing Fedora and writing image on a SD card and so on and so forth.
The idea you have is very good and I would like to work with you closely to set up a Fedora QA docs repo and then you can start writing some docs there.
Note that Test Days are events which take place in every release cycle and writing blogs about them make more sense than writing docs. Hence most of these test cases are written in Wiki
and the QA team uses Fedora Wiki TCMS to maintain its test cases.
However, if you want to write test cases for "how to test" starting with writing test cases will be a better place to start.
Let me know what you think?