I'm still on 18B, so don't have Apple Carplay/Android Auto. I don't have any burning desire to get it upgraded, so probably wait till its first service.
With the voice control, I mainly use it for navigation, "Go home" and "Go to postcode" are the most useful. One thing to note though is that the navigation is stated immediately, rather than letting you choose alternative routes as you can when you type in the destination or select from your favourites/recents.