Nice job. =) I like to start with sketchup to get the basic blocks and shadow positions, then export a 2D view to photoshop for all of the actual drawing work. At least for me, it's a lot more fun to get the gritty perspective stuff over with so I can concentrate on playing with everything else. Using the group function makes it easier to move, rotate, and multiply objects in sketchup. And it does have a freehand pencil tool that you can get from the drop menu (useful for city walls between towers, and rivers that aren't straight canals, and some roads and odd buildings). Anyhoo... =)