Well, you could have work a bit more on the overall looking of your map.
Everything seems to bright, the same light is used everywhere, some texture should not be used as a wall (screenshot 4 and 7 for exemple), some parts seems to be "dull" like that long corridor.
So, you should add more decals here and there (posters, trash, signs...), even trash models. Also, you could use differents light tones (for exemple clear yellow for the corridor and grey for the cells...) and differents brightness. Same for the textures, everything seems too bright. Try to use darker textures for the floor or the ceil...
It's just my humble opinion, but I'm sure that you can do even better aesthetically !