I can't believe all that room treatment has done nothing to improve the sound at all, even in a bad room. I assume you were at least smart enough to ask GIK to help you figure out the right way to treat the room, and you didn't wing it yourself. If my assumption is right, I'm stunned that you got zero improvement. Does not compute, even in that square room you have.
Anyway, I'd open up the Seattle area yellow pages and see what you can find, phone a few of them up and talk with them. Also try googling Seattle acoustic consultants etc.
With all the money you've spent, and the investment you've put in to room treatment already, its good to see you're not giving up.
One suggestion... make sure you get the right kind of speakers for that room. Speaker integration in to the room is critical and comes before speaker placement and room treatment in my book.
And, have you considered a reno of the garage/room to make it more rectangular? That might be the best thing you can possibly put your money towards. And don't sell those GIK products either.
