@tkearsley I’m not sure I understand the issue you are describing… a “document” in the Discourse Docs plugin is just a forum topic with reply posts just like every other. You can edit any of the “document” reply posts underneath the “document” topic, as well as the “document” topic itself.
Also, you can limit your “documents” to one specific category, and also assign specific tags to that category…
You don’t “promote” a Topic, per se. This is how you do it:
In the composer (while you are creating or editing a Topic), you assign that Topic to a Category which you have designated in the Discourse Docs plugin settings.
The limitation (just like every other Reply post under any other Topic) is that when you are Replying to an existing Topic you cannot set or change the Category. If you have the permissions to edit the Topic, you can change the Category (in the composer) while you are editing the Topic.
You can grant that permission to other users (or an entire Group of users) to change the Category of a Topic by granting them permissions to edit that Topic.
However, remember that (unlike Tags) only one Category can be assigned to a Topic.
I am not a fan of editing the original post. Not sure how our developers would feel if we went in a rewrote their topic. We want to have the ability for our technical writers to take the content of a solved topic and craft a professional KB article.
I was able to do this with Lithium years ago, it was a great feature to have.