Attached Link: Atomic Knights

This bridge was made in Max and is heaviely inpiried by the painting "In search of forever" by Rodney Matthews. It is one 3ds object ; with 3 bitmaps. Still the bridge looks to artificial. What can be done to make this look more realistic ? Is it possible to add different Vue materials to the bitmaps without splitting the bridge back to parts ?? Please give comments, every hint can be usefull.