Yeah, I'm digging that rough mockup. Really cool.
You seem to be using diminishing perspective, which will give you prblems if your character walks around the world enough and everything pans. Angles will get more and more extreme as she gets away from the central points. I'll just have to wait and see what you're doing here.
Also, you're already using this type of perspective projection:

Are you going to mix perspective types for this game?