I'm still not completely happy with it, anyway I opted for OpenMediaVault 5.
I Installed on it MergeFS and SnapRaid, basically is the same solution without many whistles.
OMV is based on Debian and it is more open to any need, if you need a packet you are free to install.
I have fear of "closed" solutions like unraid, is not a matter of price.
I'm also not happy of what I found on this forum. I think Unraid is a great work but more suitable for an home media center. Different uses are seen with diffidence.