Congrats on your placing! Great job! I'm not a hunter rider, so I don't know exactly what hunters look for. But from a jumper/eventing standpoint there are a few things I would work on. As a note before I start, all of these things are minor. The elbows are the only glaring thing that I would try to fix right away. Your overall position is really very good and very appropriate for the height that you're jumping. Just as you move up the levels, these are some things to think about.
The poster above me mentioned that you hold your hands really far up your horse's neck. That's because you don't bend your elbows hardly at all. There should be a straight line from your elbow through your hands to the bit. You almost have a line from your shoulder to the bit. To work on that you should really focus on bending your elbows so that your upper arms are closed on your sides and hang comfortably. You can also put a crop in front of your elbows and behind your back when you ride. (If that makes sense)
Sometimes when your horse takes a long spot you get left behind and catch him in the mouth a touch. It's not over every jump and it's not awful, but it's something to work on. Over all I'm under the understanding that hunters want the takeoff points for your jumps to be smooth, right? Your spots to jumps are a little inconsistent. (Which is completely appropriate for your level of riding, these are just things to think about for the future) To work on improving your eye I suggest that you count strides to the jump. Ex: 3, 2, 1, jump
You can also put placing poles one stride in front of the jump (9 feet) to help you know when your horse should take off.
There seems to be a trend in your riding that you get your shoulders too far forward. It's not a lot, just a smidge. This can sometimes cause your lower leg to swing back. You seem to do it a bit more when in the last few strides approaching a fence, as if you anticipate it. Often times just thinking about pinching a pencil between your shoulder-blades can help you fix this. If you focus on rolling your shoulder-blades back and keeping your heels underneath you you'll find that you can eliminate this tendency pretty quickly.
As a little side-note, your overall position will always be strengthened by lots of two-point and no-stirrups work. (I know, I know, I hate it too.)
Overall it was a lovely
round! I love your horse and the two of you seem very well matched. Anything that I said today is very nit-picky, just some general recommendations for future improvement. Keep up the good work!