@ neotic
Outside needs the most work imo, windows to the buildings and breaking up the texturing of that gray/yellow building in the background would be a good start i think..
The area outside the mainbuilding(?) is much to open, for that ground texture atleast... Maybe add some small buildings for security or something?
Also needs some props... lightpoles, electricity thingies (cant remember what they're called) perhaps?
As for the inside theres not much of it in the pics, but from what i can see you should try it out with less natural light and slightly yellower light from the fixtures as there arent any windows that i can see which would let the natural light in.
Also, build cubemaps, doesn't look like you have judging by the couch inside.