Brian that would be my dream space 2600 square ft!!!! I just checked out your pictures you have got a nice looking space there too!!!
We only have around 1000 sq ft but I don't find building to be that much of a chore or even that much of an expense. When you are out in the country then its no so much about ploughing loads of money into sound proofing which is generally what costs the most.
Putting up walls, windows and panel absorbers is fairly cheap in the grand scheme of things, plus with our place we have been there for 18 months and we are on a long term contract we don't plan on leaving anytime soon. In fact there is more chance we will be expanding into the barn next door and knocking the walls down in between the two so we can expand our space. Then we can add a another live room with higher ceilings and vocal booth to our set up!
But I guess thats all in the future as the space comes available.