You look to have some long legs, girl! I'm short so when I ride, especially jumping, my legs look even shorter. :P
Let's start from the bottom up.
You heels look pretty good although I'd like to see your toes pointed more forward to help roll your leg onto your horse. The stirrup length you have in these photos is good for flat work but I would put them up atleast one hole for jumping. Actually I don't think you should be jumping this high but I'll get into that later. I like your leg position for the most part while you're jumping because you keep it somewhat underneath you but on the flat, blehh, you need your leg under you.
Actually, what I want to continue on just won't make any sense until I say this, you really need to go back to the basics and solidify your "foundation." You should be able to keep a correct position without relying on the horse's mouth. On the flat you are asking for too much "face" from your horse. You have her way behind the vertical when trotting and then her nose is sticking out. Work on your position first and then you can ask your horse to get into the correct frame and work from behind, not just trying to make a pretty picture by tucking her nose in. When you are jumping, you are either relying on her mouth for support or having no contact at all. Again, go back to the basics and focus on yourself. You will find that if you work on you first, your horse will follow.
I really do like your upper body when you are on the flat! You are sitting up tall and looking where you're going.
Opportunity is missed by most people because it is dressed in overalls and looks like work. ~Thomas Edison