Wow, great atmosphere, Blitzkrieg.
Very good, Archie! Your textures are getting better. I like the structure. Nice play with those lamps. Try making one of them more yellow or more blue, it happens all the time in real world. Now, what does it need? You probably don't want to waste such a spacious hallway. Add way more air/duct/vent shafts or whatever they're called, more different pipes in sizes and colors, some vertical too, maybe some valves too. Some wires hanging and an electrical box somewhere. But what would really kill the repetitiveness is some nasty staining, dirt and rust both on walls and floor.