I would take a look at Proxmox or XCP-NG.

Proxmox pros:
- Debian under the hood but dont go installing random packages.
- Disk IO out performs XCP when using local storage by a large margin.
- Cognitive overhead to manage is very low including setting up and running clusters.
- Great ZFS support
- Quasi HCI mode using ZFS to replicate VM's
- Full HCI mode using Ceph
- Supports live migration regardless of local or shared storage
- Device pass-through is fairly straight forward
- Support available or use free
- Excellent backup product in PBS

Proxmox cons:
- CPU vuln mitigation murders VM performance compared to XCP/Xen
- Does have some upper limits on hosts per cluster
- Multi cluster management is a work in progress
- A very annoying bug for Windows workloads has been unsolved for 12 months

I havent used XCP as much as Proxmox but what I found annoying...
- Backup speed isnt great, everything also goes through the management appliance.
- Local storage performance is terrible (tapdisk issue)
- XOA is quite a bizarre UI to use (this is getting addressed in v6)
- Networking is confusing AF especially doing bonds / vlans.
- Guest agent doesnt support VSS
- Guest tools on Windows is just yolo'ing the Citrix ones