Hey there !
Your texture is far too dark. It'll be a pain in ass to light a room with such a texture since it'll "drink" all bounces.
Futhermore, for now, it looks more like a metal overlay put on a basic modelisation more than a real metallic texture. You need to add more details (seams between plates, screw, scratchs, etc) to make it more credible. The dark yellow splatter you put isn't appropriate at all too =s
Try to study how shiny a metal could be according to its roughness, it could bring a lot into your work =)


