Just a quick diagram of the altered layout we were talking about earlier. Each area has a different atmosphere based on it's location within the building.
With this altered layout, we planned to reduce the number of corridors in our level and instead replace them with more interesting rooms. For example, the long decontamination chamber has been shortened dramatically, and the machine hall corridor has been almost halved. In it's place, a new basement area has been put in to provide a transition between the machine hall area and the atrium area.
Some doodles of the starting areas and the proposed new basement area.