473 poly's is not much. but when I look at your render i see you can bake some details into a normal map. that way you can make more stuff in your coridor without making the polycount higher.
Also if you make a game for the pc, you shouldn't worry to much about the poly's most pc's can render atleast 50.000 poly's onscreen realtime most even more up to 2 million polygons. if you making a web game their are diferent rules ofcourse. (aswell for iphone/ipad)
