Wow, Keedo, that IS a tall order! Intriguing, though, so I wouldn't be flabbergasted if someone actually picked up the gauntlet on this one. Let me also suggest that you give it a shot--at least in creating some basic shapes and visuals of the city (even if only in Paint, hand-sketches, etc.); it would perhaps be much more interesting for a cartographer to improve and refine your attempts than create from scratch. Just a thought.