My attempt at a studio layout

Hi Everyone, To echo the common sentiment, thanks to all of you, but especially John for providing such a great resource. I've been trying to come up with a plan for a studio that will be built in a seperate building, starting with nothing but dirt. It will be located in a rural environment a small distance outside of Canberra, Australia. Therefore complete sound isolation isn't too important. The studio is not intended for commercial use, just my own projects and occassionally friends bands. The idea is to end up with a useful environment for tracking and mixing electric guitar, bass and drum oriented music. Typically each instrument would be tracked seperately. although as mentioned above it is likely i'll track a band every now and then, so some isolation of drums and amps would be useful. Having said all that, jamming with friends is important to me as well so I can't have a drum kit on one side of the control room and a live room on the other. The plan i've attached is one of many attempts, so far I like it the most. I guess my concerns about this plan are the lack of line of site into the vocal booth (not a big issue given my objectives), the doorway between studio A and B and the glass to the outside world in Studio A. I also fear there's a glaring error that i've over looked and that it's not the most efficient use of the space. With this layout I imagine i'd have studio B as a fully floated drum room and the control room fully floated. I envisage being able to open up the doorway between studio A and B with some kind of concertina type door to facillitate jamming. I also like the idea of a concertina arrangement with the glass external wall in studio A so I could open up the entire side. As it looks into the garden I figure it would be a nice outlook and as i'm not concerned about annoying any neigbours or capturing the sounds of vehicles etc I can't see any down sides. The overall size of the building I have in mind is L=12m W=8m and height=3.6m, these would be internal dimensions. This isn't set in stone though so if I need to go a little smaller or larger then it's no problem. If anyone has any comments, advice or suggestions on the layout they would be greatly appreciated. Thanks Dominic