What will they be recording? Is it music, or spoken word for radio or what?
I ask because the design of the control room is still bugging me. If you are just mixing down to mono for AM radio, then a lot of problems go away, but if you are trying to produce good music in stereo, you need to be able to hear a good balanced sound in the control room.
Offhand, I wonder if it would work better to get rid of the third vocal booth, and to use the area for a larger, symmetrical control room. That way you can put the monitors in a position where you can have a good balanced stereo field.
Yes, the downside is that the control room is rectangular, but with the right treatments on the walls to control reflections, and bass traps in the corners, I wonder if it could be made to sound good. I defer to the experts around here -- this is just my guessing.
How high are the ceilings in the rooms?
-lee-