If my next turn isnt for half an hour, being zoomed in to the road doesn't give me any information I can't see out the window. If the next turn isnt for a while, zoom all the way out to top down view so you know where you are in your journey. As you get closer to your next turn, goto the regular view so you can see upcoming street names to help you prepare for the turn. Then when you're approaching the intersection, go to a top down zoomed in view (like google maps)