Most of the sticks I use are 20ft and the base of the stand is right at the top of the sticks. I get about 18ft with my mobile setup which is a Millennium M100 and 4 Muddy climbing sticks.
18 ft in my lock- on’s and 15 to 22ft in my climber depending on cover. Have missed by climbing to high and didn't have any more advantage than being at 15ft.
I always stay between 15-20 up.. I use 4 muddy sticks as well (as stated above) and could probably get a bit higher but to high causes me to much of a angle shot that I'm just not comfortable with....I normally don't have issues with cover so needing to get higher isn't of any benefit to me either...when I hunt Public land I try to scope out trees with plenty of cover