Advice on my scene: dark lit room

Greetings,
I first posted this to lighting and rendering but realized it is a question more suited here.
I plan to put the following scene as a main menu background for a personal project of mine.
I haven’t added the particle effects and god rays just yet as they would steal the eye from my question: lighting and composition.
The floor is pretty much done, but the walls are not nearly good enough. Any advice on camera placement and light rig? The goal is to be gloomy here.
Note that the floor is rendered separately from the walls.
the first image is how I placed my lights.

http://i1268.photobucket.com/albums/jj563/agiro8747/roomOnly_zps9j6wcwgd.jpg

second for a sharp(unblurred) background
http://i1268.photobucket.com/albums/jj563/agiro8747/roomSharp_zpswualibco.jpg

lastly what I have now:
http://i1268.photobucket.com/albums/jj563/agiro8747/part1_zps8jjosqmk.jpg

all the help appreciated.