All the categories already have topics with what to write pin in them like…
These are however a bit allover the place with having too short descriptions and others putting a wired template for writing posts.
The only problem with your thing is that it will just sink in the timeline and new people will see it. There is also this wiki thread with a lot more Wiki but it has the same problem, new users just wouldn’t see it. You would need an admin to permanently put stuff like this somewhere where, especially new, people will see it.