I was recently working on my game that is about to release, Blind Raid. I have a menu screen for it and I decided to take a shot on building and lighting skills. I’m proud of what it turned into!
It does look pretty dope, but I would add more decorations around the place and maybe make the light flicker somehow. Also, If you made that NPC look like a Drill Sergeant, that would give it a more military look. Apart from that, amazing build!
Its nice however the detail between the room itself and the guns / ammo crate on the table contrast too much with the different building types making it look very odd.
Considering that one of the (presumptuously) gun lockers is rusted, I would make it so the room is degraded as well - if I were you I would achieve this by adding cracks in the walls, weed going through the roof and the walls, potential vines draping down and rust on the other lockers as well.
To add more variety to the lockers, I would make one partially opened so that you can see the contents within - more guns etc.
The walls are very bare and empty - so you could even add paintings, shelves on the walls for more ammo crates, even more lights and a door.
Use this photo as a useful reference for improvement.