As yet I have no back story for this starship. I do imagine, though, the huge dome shield in the front not necessarily being to ward of incoming laser fire, but to shield the ship as it enters intense ion, electrical, or other energy storms in space. This may eventually become, in one of my stories, a science ship of some sort.
The command bridge is in the small dome sitting atop the tube-shaped hull. Facing forward, the flight crew are not necessarily blind past that mammoth forward dish fore of the bridge, as sensors and cameras situated across the dome send enough imagery back to the bridge to provide a clear picture of what is in front of them.
As far as the silver coloring of the hull and engines, that is not a custom color of Lego bricks, it's metallic enamel paint.