Some form of domain and a DNS server (router or Pi-Hole) in your LAN

zfs send

Proxmox is pretty much focused on ZFS, LXC containers and VMs. You want mergerFS and Docker. I say avoid Proxmox and go for Debian or another distro.

Only when using zfs, which op is not.

I always wondered the same about ZeroTier. If the controller is under foreign control, isn’t the whole network compromised?

Be careful with compute intensive tasks. Some providers don’t like when you actually utilize your rented hosts.