lemme see if i can do this again, i am a bit out of practice in my critiquing.. my advice, for what its worth, dig up some of my old critiques.. they are numerous and pretty indepth, some might answer a few of your questions.
this room/area.. its a box, with stuff tacked to the inside walls, not Incorporated into the room, but glued to the walls ans such.
make alcoved for the valves, make indentations in the ceiling for the door.. make the floor multiple elevations, in other words, don't just attach everything to the pre-existing walls.. make them look like they belong, not added to fill in space.
hope that made sense..