Currently client group management allows only individual client's IP address or a subnet in CIDR format to be specified (at least in the web interface).
It would be convenient if IP address range can also be allowed as one of the input format (such as 192.168.1.120-192.168.1.125 and 192.168.1.180-192.168.1.190). Internally it could expand the host ranges and generate individual host entries if needed.
Some firewall, like pfsense, allows specifying host aliases that way.
Just something to consider.