I go for the short cotton karki shorts right up until I can no longer feel my legs through cold and then switch to the old brit army lightweights....but I have to agree about their lack of fire resistance...I once saw a guy with his melted onto his legs, it looked horrid but then he should have known better than to play football with a parachute flare!!!!
If you can hold out from the cold with shorts you'll do just fine, nothing in the world is as waterproof and breathable as our skin....speaking of skins...
Does anyone ever try to make leggings out of the skins from the bunnies and squirels you all seem to be shooting? ? ? I'm told buckskin leggings and shirts are ideal outdoor wear....sort of Tom Brown Jrn style!