putting up a ZFS storage

I'm putting up a ZFS storage on an old R720 Server with the PERC firmware reconfigured to allow direct disk access. this machine has 8 1.8TB sata disks. I'm gonna use it to serve disks for KVM and XCP-NG Vms. What would be the best pool setup for this old bunch? I was thinking about mirroring it in pairs, but I don't know if this would be smart at all.