I went from OMV, to TrueNAS, to just mounting the drives directly on my Proxmox host, combining them with mergerfs, and then sharing them from a samba container they’re bind-mounted to.
Unless you have some fairly complex storage needs I’d say go with a good hypervisor over a dedicated storage OS with a hypervisor tacked on.
For me it has always just defaulted to the left-most monitor. I had a script that would disable that monitor with xrandr when sddm loaded and then re-enable it on logon, but I couldn’t get something similar working in Wayland.