Ah, looking interesting. Nice stuff. Supposed to be a Greek temple or such?
Only thing I'd say is that the floor in shot 3 looks too flat, while the ceilings look very natural with those height and shape differences. Perhaps upping some floor parts and putting small steps between the different levels, just a small height difference.
Perhaps you should also work on those stone textures somewhat, they get repetetive after a while with those yellowish shades. Nothing too worse, but could get improved on.
Oh, and in shot 4, I'd say putting some lighting on that large symbol on the wall would give a nice effect rather than putting in light beams from the top only.
Keep it up man.