Thoughts:
The spawns in the water closets seem bad because there's no weapon handy.
The observation area seems useless. If it's a dead end, and no items spawn inside, and you can't shoot through the glass, it may as well be locked off.
It doesn't seem good that you can see clear from the elevator into the experiments room, for gameplay, optimization, or logic.
It seems like there are already too many secret passages, and this is only half the level. It might be better to just have a tight hallway running from the warehouse to the stairs/security and leave R's office a dead end.
There should be another way out of the experiments room, or the hallway between there and the wind tunnel. As it is, a player can seal off those two areas just by controlling the hallway. If the upper level goes this far south, this area might be a good place for a third stairway.