Can't speak to Alaska but in general, plus-one on going bigger than you think at first. I went 24x32 and wish now it was bigger. Pour a thicker slab than minimum code. Good buildings start with overbuilt foundations.
If I were doing it again, I'd do gambrel roof (barn style) and put a loft up above. Also, even if you don't plan water, when you trench the electricity to it, do yourself (or some future person) a big favor and lay water pipe in the trench too. Just leave it empty and cap it off. Even with no formal drain lines put in (of course they'd be good too), a simple redneck mini-septic that can handle one dude washing hands and taking the occasional dump is not expensive or hard. At least in Oregon. My shop is below our septic system so it'd be a pain to get drains up to it...... which is why I didn't run water to my shop in my electrical trench.... and which I have regretted many times since.
Uh... what else. Go way oversize on your garage door. Spend the extra dough to run good high-amp circuits. No #14 wire for you!
