Honestly, Lingon, I'm conflicted. The old-school RPG fan in me desperately wants a map in your Exculta Mundi style.

Unfortunately, due to the nature of the game engine, we're going to need an actual heightmap eventually (and don't get me started on the headache that is Skyrim heightmaps). And that tells me that a photorealistic map would be money better spent.

Oh and additionally there's going to be a lot of questions the development team's going to have concerning the actual physical structure of the map itself. How to reach a comfortable space in game flow (as in the actual path the Player will take through the map) and somehow also avoid a blatantly hand-carved map design. For example: nearly every map we've done on our own, for conversation purposes, has been rectangular. 'Cause that's the shape of our monitors, you know?