I run my own server, not sure on post retention or image size or even number of images. But you can make it so that only you can make communities, you can even make communities admin post only.
I would give the docs a good read and maybe have a look at the GitHub repos
I use passkeys and find them great, mind you I know that you need at least 2 of them so you have a backup. I also use yubikeys at work and they are the same issue, you need 2 of them in case 1 breaks or gets lost.
Maybe the setup should be, make sure you have 2 passkeys on 2 different devices? but not in your password manager
Home Assistant has a lot of moving parts, all the add-ons and extra user stuff. So they provide a docker image with everything you need, they also provide a full appliance install for easy setup.
If you did all that as a package install, you would complain about all the dependancies and if you didnt install the right version of something Home Assistant might not work at all
I have a single network with my jellyfin server and wifi devices, I run Pi-Hole with DNS for internal things and can use Jellyfin while at home or out and about.
In Pi-Hole look for Local DNS Records to add your own suff
maybe its just me, but self hosting is more about learning to run and then simplify my setup. Thats why I read the documentation for the project I want to deploy, then see if I have anything that looks similar. But as I've been doing self hosting for almost 20 years, plus working at a SaaS company. I have done a lot of things with a lot of different tech
All my docker stuff has a very common look to it, also I have tried a lot of stuff. See my Git repo with some examples -> https://github.com/mhzawadi/docker-stash
I think you can make a template from the helpers page, see if that works