Hey, its always good to ask for critique to improve yourself. The one major flaw that is sticking out if your leeg is way too far back. You are putting yourself in danger of falling into the fetal position if your horse were to spook, and ultimately its easier to fall in this position. Imagine holding a yard stick at your shoulder. Your shoulder, hip and leg should all be perfectly aligned.
It almost appears that you are bracing yourself with your knees. Try some excercises to open your hips and knees. You can do this at walk, just take a deep breath and widen your knees and press into your heels. The part you want "hugging" your horse is your calves. Your hands look great and your posture is good, just keep working at it, but bring the bottom of your leg forward.