I'd like to create rules on interface classes (say WAN-1 and WAN-2)
This way, if I setup some FW rules, or QoS rules etc, I can apply them to the Interface-Class/group instead of two individual rules applied to specific interfaces.
[Making changes to multiple rules for each individual interface (IF) is prone to error, should changes occur to a rule, and you have to duplicate the change to multiple IF's.]