I like it. I have to say that the style can be very effective - hand drawn 3D is precisely how I would describe the corpse-bride buildings. On the other hand, probably not so useful from a mapping point of view. Your actually hand drawn work is probably quicker and better. I suppose using sketch-up to get a basic layout and then doing a hand-drawn paint over filling in all the detail would be the closest to actually using it for a 3D sketch.