Thanks for this post. As I'm sure you are aware, @ned and others are working on several related wiki projects.

In your post, you said:

Steemit should either pick one of the existing wikis or start their own.

In my opinion, this really is key. Steemit will need to consolidate all the efforts from the various wikis that are out there, and make one official version for the site.

I included this with a link to your post in my list of proposals to enhance the Steemit website :)
https://steemit.com/ui/@timcliff/let-s-make-steemit-better-comprehensive-list-of-suggested-ui-ux-improvements-to-make-to-the-steemit-com-website