Built a NAS over 5 years ago. It runs UnRaid and configured with dual parity. If a drive were to go bad: shutdown the NAS, slide the drive out, slide the new drive in, power back up and the rest could be done remotely (via your WireGuard tunnel).

Unraid is capable of hosting your VMs and/or docker containers as well. I have Syncthing running in a container with a remote machine (also running Syncthing) and they sync backups.

One of the main perks of UnRaid is that you can mix and match drive sizes. You just have to make sure that your largest capacity drive(s) are your parity drive(s).