Updated floor plan. Now it's 2 doors separating the control room and iso booth.
X-Ray floor plan. Note the double doors and the window between the microphone in the iso booth and the mixing desk.
View from the singer position in the vocal booth. I angled it downward a little so you can see the microphone. The mix stand model is a little short by the way, but the window placement seems about right.
View from the mixing position. I might make some virtual cardboard cutouts of performers so I can imagine it better. :D
Standing where the couch meets the keyboard do give you an idea.