Is the ZFS “plugin” reliable and user friendly? That’s my only personal trepidation for switching off of TrueNAS. The easy webui for ZFS scheduled maintenance and general configuration are super nice.

Do you have an Intel ethernet NIC? That’s a known issue, in particular for more recent Linux Kernels used in Debian distros. This also means it extends to TrueNAS, Proxmox, etc. There’s a known fix for it too (or you could just downgrade the Kernel).