My setup is simple:
- Pictures: I don't take many and rarely look at them tbh. So they just sit on my laptops NVMe
- Music: I only ever use cmus for listening to music => Therefore music is also only locally on my laptop, managed with beets
- Movies/Tv Shows: I have jellyfin running on a raspberry Pi 4. For single user use this works fine (even transcoding DVD quality works). For multi user or higher resolution transcoding this probably won't work.
- Backups: One off-site backup at a cloud storage provider using restic and one backup on a USB hdd I simply plug in every other week.
My recommendation is: Keep it as simple as possible. In the past I created the craziest setups, but it turns out that in every day life I have neither the time nor motivation to maintain that shit.
I think this somewhat depends on how tech savvy the people you want to give editing access are. If they know how to handle git and write markdown, I'd go with a git repository with (for example) mkdocs and setup CI/CD to automatically deploy to Github Pages. This would be free. If they are more like the typical MS Word andy, I'd go with a self hosted instance of bookstack. You could host it for example on fly. Unfortunately bookstack does not (yet) support sqlite so you'll also need mariadb, which will make hosting it on fly slightly more expensive (but probably still far below $10), because you'll need 2 machines in total. One of which you can't scale to zero. There are probably other cloud providers where its going to be cheaper though.