If an existing page could use extending, refactoring, or correcting, but you don't have time/inclination to do it, please add a FIXME note on the page.
If you:
…you could write it yourself once you have editor rights to the wiki. That would be awesome.
However, that can be a heavy lift, so if you don't want to write a page yourself, you can add ideas for pages which would be useful additions to the wiki below, and someone will pick it up.
It's OK simply to list the idea, but if you can add links, references, or background, please do.
Create a new page on the wiki when one of the following opportunities are present:
Avoid creating stub pages where none of the above are true, or users will find the wiki full of pages which promise much and deliver little. If you have an idea for a page which should exist but you don't have time/inclination to improve content, links or deduplication, list it on this page instead. Link to the non-existent page, and either you or someone else can come back later to get the page started.