I usually set my own deadlines for projects, this way I can move on to different things. Due to these time constraints I won't be doing the whole map, just everything seen in the concept piece.
Thanks for the suggestion, I'll scale it accordingly before doing the trees.
The background in the distance is a static mesh plane with a screenshot of New Alexandria from Halo Reach. This is just a placeholder for the moment.
Also, what would be the best way of achieving this kind of light effect in UDK for my floor?