I tend to stay on the low end of things -- 16 feet, sometimes less. I've gone higher, and twice single-lunged deer with an arrow. The lower I am, the better the shot angle, with archery equipment. I pick a tree (preferably a cluster of trees, or a multi-trunked tree) so the concealment is there, without necessarily the height. If you're talking anemic, skinny trees, going higher is sometimes the only option.
This past monday I had three does from my 13 foot high stand pass directly beneath me. At least two of them were old enough to know better, and they never had a clue I was there.