I'm a big fan of minimizing the analysis of technique and just getting out there and learning as you go, as long as you're doing it in a safe and ethical manner. But I will share one tip for elevated shooting almost nobody ever does.
Just like your more common practice on a level shooting range where you progressively back up as your consistency improves, you can do the same thing with elevation..move a step up the ladder and shoot from that elevation until you have a better feel for the angles and arrow trajectory versus your "normal"line of sight, then move up another step ,and continue this way until you are well-practiced and confident at all different elevations. Along the way, you will learn that there almost never a predictable shooting position when you're in a stand and you will get more comfortable with the twists and contortions that you have to with your legs and lower body to get your shoulders into good alignment for the shot...those dang animals just wont follow the script and hit their marks! As others have mentioned, a 10 yard shot from 16 feet up is a steep angle, but veteran tree stand hunters do it all the time.