Suggest in the example you've given, that the pilot waits until ready for push back and start, requests clearance from ATC, informs CC to arm doors, turns on beacon, runs the starting checklist.
Massage the order as required to fit with other SOPs, but I see no reason why the beacon must be on before the pilots are ready to go.
If the beacon is on, the pilots are ready to go, and all vehicles must bugger off.