This is probably a bit too custom, but I did the same, and it works really well after it's set up. Plex/Jellyfin just works for everyone (you do need to use the app, because I disabled transcoding).

I have a repo that uses a Harbormaster (a Comppse-based deployment tool I wrote, https://harbormaster.readthedocs.io/) to set everything up and keep it up to date, so all you need to do is run the Harbormaster container, point it to the above repo config, and the apps will run. Then, you just need to configure each app, but the directories will be set up properly.

It's a bit of work, but probably not as intimidating as it sounds.

https://github.com/skorokithakis/mediacenter-in-a-box/