I noticed that both Chinook (timed crate drops) and CargoPlane (air drops / supply signals) announce the drop location as soon as the aircraft spawns. Would like to get a config option to disable the coordinate portion of this announcement.

If you set Location -> Show Coordinates to false in the config, they should not be showing.

Right, but this will disable coordinates for all alerts and not just the very first ones. I'll probably just hack on the language files like you suggested in other threads.