Like someone else commented, shorten you stirrups and hole or two, you're reaching for them. I would say to sit back, your shoulders have tipped forward (probably because of trying to reach down with your lower leg giving you a weak upper body) and now our whole center of gravity to too far forward.
You already mentioned your hands, so I'll leave those alone.
You look stiff, relax and I think everything will fall nicely into place. I love your elbow angle! The fad now-a-days is to have them forward with your hands on you horse's withers. You're looks great regardless of the hands. If you relax your shoulders and don't lock your hips up, you'll look really, really nice.
Someone already pointed this out, but I'll hit on it again; your horse is behind the vertical/evading the bit. It is a very nasty habit and you really will want to make sure it isn't a common occurance.
Overall, I think you look decent. If you raise your stirrups a couple holes I think it'll be much easier for you to fall into a more comfortable looking position. :)