We just made a decision on what we are going to build this summer, too. We'll be building a 28x42 carriage house with 20' sidewalls. Three 9x9 overhead doors, on the main level, and ~1,100sqft of finished living space on 2nd story. Fully insulated 1st floor (and 2nd, obviously), with white steel paneled walls and ceiling. All steel exterior skins.
We wanted to put up a new home on our land, but have now decided to go this route, instead, to allow my wife the opportunity to take some time away from her career (as a school teacher), to care for our two young kids. When the kids get to school age, and she goes back to work, we plan to build a home, adjacent to the carriage house.
It's pretty exciting to dream up some plans, and think that, in just a few months, there may be a brand new structure (cabin/barn/home) on your hunting property!
Post pics of your project! Rest assured I will.