The simple voice command "map" will display the map in whatever configuration you last used it.
So if you always use it in direction of travel mode, you don't have to say "map, direction of travel" you can just say "map."
Also, for me, the map is what I almost always have on the nav. So pushing the iDrive controller to the right and holding it there for 2 seconds switches to it. I tend to switch back and forth from the map to the entertainment (MP3 CD) screen (pull down on the controller and hold for 2 seconds to get there). I like the "push-hold" shortcuts rather than voice commands for that. YMMV.