I think you look okay. All though to me, it looks like your position is forced or you're trying too hard.
For my taste, you are lying too much on his neck. Sit up a bit. You are doing a great job of looking up and where you're going.
I like your stirrup length but I think you're gripping too much with the back of your calf and thigh. Try pointing your toes more forward and wrap your leg around your horse, not clenching him.
I'm not sure what's up with your release. In your old photos, you're hanging on him as well as in the first photo with the hackamore but with the other hacakmores photos, he looks great without you hanging on him. I think you could definitely start practicing an auto release.
Opportunity is missed by most people because it is dressed in overalls and looks like work. ~Thomas Edison