[Feature] Split with choice of "Only ..." and "All but the following networks/hosts"

Noodles156 described in https://community.sophos.com/products/unified-threat-management/astaroorg/f/62/t/57314 how he used 32 network definitions to send all traffic therough the RED tunnel except that destined for their VoIP provider.

When "Split" is chosen, a second dropdown menu with the choices "Only the following networks/hosts" and "All but the following networks/hosts" could appear.  I assume you're just writing routes, and this would allow a simper configuration file in such cases.

Cheers - Bob