I decided to insulate hives. Bee boxes, even thick ones like mine are a poor substitute for bee trees. The results are encouraging. I figure the bees are under enough stress already dealing with mites and viruses and I want to ease up on them in other areas. I might go for more winter hardiness after (if) the mite hardiness settles into place. Even then reduced food requirements (and less poop produced), better spring build up makes it profitable to insulate.