Couple things. You said you were gonna add detail but I think you left yourself a little too much space between the pillars and too little space between the pillars and the walls. Might want to fix that or the pillars just kinda looked crammed up again the walls.
It seems like an okay start, but the walls have been obviously duplicated. Make sure that when you add more detail and props and stuff, that you draw their attention away from that stuff.
Can't really rate yet, so Ill just wait for you to add more :P
Not much more to say other than that.