There are a few things that are currently hardcoded in the traffic splitting feature:

• The gateway name that is attached to VirtualServices (and it's namespace name)
• Exposing the ISVC outside the cluster (forced "true" at the moment)
• Hostnames of the ingress gateway
• Constants (like port numbers, service names) used as in-place strings in the code. These probably should be moved to global config/constants and use those global variables.

All these values should be moved to static configs, or to user-customizable configs. The final values of several of these symbols are unknown at the moment, and moving to configuration means that the amount of needed code changes will be reduced (or fully removed) as the service mesh integration evolves.