Steve, the office building looks great! As an architectural buff specializing in modern office architecture, I can tell you that the bare steel looks very convincing, although you must "dull out" some of its reflective properties. However, should you decide to paint it, may I recommend an off-white color or concrete?
Finally, maybe a small corporate logo on the very top brow of the building would give the structure some character? I'm really liking this project, and look forward to more of your updates!