Hi, the only thing that looks off to me, although it only shows in the flat example you show, is that the level of wear and damage you show on the tiles, I think more of the polished tile surface would be worn away. For example:
Trying to recreate Adam Adamowicz's Fallout 3 dart gun based on his concept art for that weapon. Currently on retopology, will sculpt in some metal damages/scratches on Zbrush before texturing in substance.