Dunno about region coding. No idea actually.
Map interface -- the map takes up a lot of the screen when you bring it up. The world map looks pretty much like the paper map that comes with the game, and the local map is kind of an overhead view that also looks hand-drawn. You can't make notes on it, but you can put a compass marker on the map, and you'll see an arrow on the compass that always points towards your marker. Also, most locations -- settlements, dungeons, mines, shrines, etc. -- have marker icons that appear on the map when you discover them, and you can hover the cursor over each marker to get the name of the location.
Also, in the journal you can look at the journal entry for the current phase of your active quest, and there's a Map button on that page. Click the button, and the map shows up, centered on the quest location. So it's very easy to remember where you need to go for specific quests. So hopefully that's enough so that you don't really need to annotate the map anyway.
First vs 3rd person: I play in first person all the time, except when I'm on horseback. You can't really aim for ranged attacks in third person, though melee can work OK. But when you're on horseback, you steer the horse with the controls that make you strafe when you're on foot (A and D on PC, left analog stick on Xbox 360) and you can freelook with the mouse or right analog stick. So you can look around quite a bit while you're on a horse.