Upgrading from raspberry pi

I am taking the plunge and upgrading from my current Raspberry Pi 4 to a proper computer. My current setup is via HAOS on the pi 4. I’m planning to setup my new system with OMV as the base, and HA in docker above that. Will my backup files even be useful without supervisor? Or is there a way to get OMV and Plex running on HAOS?

BTW, hardware wise I got a refurbished/second hand desktop and i’m going to strip that for its motherboard/CPU/RAM and combine with the case, PSU, and HDDs from my OMV build (and my SSD from my current HA build), this is the PC part picker for my hardware so far (doesn’t include the PSU or drives as I don’t know their model numbers without taking things apart to look), mostly selections made for convenience or price. I’m waiting for a PCIe - SATA expansion card so I’ll have enough ports to install all of my drives. No real bearing on my question, just figured I’d share.