> So the NAS runs Kubuntu 24.04 with ZFS
My experience is similar. I no longer use dedicated NAS, firewall, or other exotic distributions. I run plain Debian, and add what I need through standard repo packages. My "NAS" is simply a Samba daemon. The same box runs countless other services including hostapd (WiFi), DNS (Unbound), an email stack (Postfix/Dovecot), multiple game servers, and Podman.
> everything else in Docker Compose
I would suggest Podman instead. It is far more secure by design (rootless) and is unable to silently alter the firewall's configuration.
These days you can buy 4 bay USB-C hard drive enclosures which let you make a nas out of any mini pc. I 3D printed a 10 inch rack to put the mini pc, hard drive enclosure and switch in which keeps it all neat and looks kinda cool.
I do a similar thing. It really is functionally exactly the same, just a bit more piecemeal.
I find Proxmox to be a great host. It's Debian with a bunch of helper scripts/GUI to run containers and VMs. I manage ZFS outside the Proxmox bubble and run a privileged SMB server container to access it.
Though I really don't use the server anymore and it's probably worth several thousand dollars with the RAM in it. Been thinking of using a spare laptop with external HD bays to do the same job.
Interesting, I never tried Podman. Thanks for the suggestion!