WOW!! Radiant heating in the floor? I never heard of that in a garage. That's cool!! I really like the color of the siding, too. That'll be sharp when you get done for sure. Keep us posted on the progress!! Good luck!
Mines gonna be very similar, 28x28 with 9'6" walls, 8 or 12 feet of normal trusses over the front part of the garage for some storage room up top then scissor trusses the rest. In floor heat to boot. Just 2 9x8 doors instead of the one.