Proxmox is Debian, so much of your ideas could translate directly across. That said, I try to mod the PVE server as liitle as possible.

Proxmox makes it so easy to spin up yet another VM or LCX to handle services with its core offerings. Also google “proxmox helper scripts” to find tteck’s additional stash of ready-made LCX.

Boy. You asked about Proxmox. Nobody said anything.

How does Proxmox make it easier? Have you used it? All sorts of ways. Like, its a full virtual infrastructure management system instead of just an OS. Proxmox loves ZFS. It does many of the things you’ve mentioned here.

Proxmox does have its own backup system that can work with an NFS target or with their smart dedupe storage and replication server product. https://www.proxmox.com/en/products/proxmox-backup-server/overview

You’ve got some pretty advanced ideas and perhaps have already moved beyond the Proxmox question. But if you are curious and haven’t used it, spin up a server and give it a whirl.

Do it. Jump in. Just start with whatever you can assemble.
It’s a great way to keep your room warm.

I don’t know about the Ubuntu LCX. I don’t container much.

I’d do this with a virtual machine and TrueNAS. Those are just the tools I like to use. The TrueNAS Scale ISO will install qemu-guest-agent, so you don’t need to worry about drivers. Make sure to build it with Virtio SCSI Single disk controllers. Use one 50gb OS disk for the install. Add huge data disk(s) after the install.
Promox Disk options … SSD emulation, Discard, IO Thread, No cache … and I use Write Back (unsafe). Use the Virtio NIC.

And try it again. Hopefully faster this time.

Been working on a jukebox VM. This seems like it will mesh well. Got LMS installed. Muddling through the rest. https://community.home-assistant.io/t/how-to-build-a-lms-based-whole-house-audio-system/436016