Another factor up by us is the cold. It can be below zero during our gun season - that gets very cold very fast in a very high un-sheltered tree stand. Not a factor during archery, unless it is a late season hunt.
Not a factor where I hunt. I have hunted out of a climber when it was down in the teens, which is as cold as it gets where I hunt.
I would suggest for people that don't want to hunt over fifteen feet, you might want to go to a pop-up ground blind. I use these in areas where the trees don't get that tall, like south and west Texas, and in inclement weather.