@riceicetea thanks for reaching out, great initiative! It may be something for the Nix documentation team to help make those worthwhile tasks more visible. So far we have only gone in that direction fairly superficially with a general contributor guide, and we have some more specific ideas for contributions to documentation which you may be interested in picking up.
Expect more of that from the documentation team in the next weeks. We recently published a call for maintainers, so what we really need are people to take some responsibility. But from that we should be able to derive more tasks that one can help with drive-by style.
Edit: Thinking about it, in a sense, roaming for things one could help out with, and figuring out how to make them more visible for others is such a task anyone can start working on immediately. If you need help to get the right people look at your things, just ping me in the given context.