if you dont know the maps a navigator would be usefull playing the rally senarios with small sings and voiceover
This is a boatload of work for something that wouldn't be that useful right now, a ton of audio work already needs to be done to the game, making this right now would be a nightmare.
I feel like this won't happen until they overhaul the sound anyway. I remember hearing about how they are planning a major overhaul that will make it easier to get different sounds on each vehicle.