I use git and commit configs/setup/scripts/etc. to it. I at least have a road map for how to get everything back this way. Testing this can be difficult, but it really depends on what you care about really.

• Testing my kopia backups of important data? that I manually test every once n’ while.
• Testing if my ZFS setup script is 100% identical to my setup? that’s not that important, as long as I have a general idea I can figure out the gaps and improve the script for the next time around. Obviously, you can spend a lot more time ensuring scripts and what not stays consistent, but it depends on what you care about!

For a lot of my service config, git has always worked well for me and I can go back to older configs if needed. You can get super specific here and save versions in git, then have something update the versions (e.g. WUD)

Most of the books I read are docs on all the fuggin homelab devices & services…wish I had time to read books at this point.

HA integrated with homekit well. I like to tinker, but hate doing interface/dashboard work. I did find an auto dashboard for HA which has made our lives easier. My long term hope is to use a voice assisstant for the rest.

Since it sounds like youre handy already, i would really dig into the dashboard side since that will dictate how easy it is for your family to use.

Sure supply chain attacks are a thing, but containers aren’t the issue. Any package delivery mechanism can suffer from it. Its up to you to verify those containers and/or build it yourself

Dunno about plexamp, but Plex has an auto-scan built in. Its disabled by default, but works like a charm. It listens for new file events and general finds things before you complete a download or copy