The first thing I noticed is that I really like your upper body. I like how you are sitting back and not leaning forward. That said, there are still some things to work on. You shoulders are uneven, meaning you are twisting your upper body to sort of "point" in the direction you are going. Ease your inside shoulder back and sit up taller.
I do like that your hands are up instead of down and having locked elbows but the rein contact is all over the place. Theirs either no contact, contact or one rein tighter than the other. I would shorten your reins a bit and make sure you have even contact. There's no need to hang or pull on his mouth. He looks like a nice guy who isn't going to need a lot of head correction or jerking of the reins. A nice even contact is all you need..
A major yuck I see is your leg and stirrup position. First of all, you need to slide that stirrup out a little more from your foot. The stirrup should be positioned so that the outside bar is touching your pinky toe and the inside bar is against the ball of your foot. Having this angle allows your ankle to flex with more ease and can slightly help keep your toes facing forward. As someone else mentioned, I would recommend taking that sheepskin off the saddle pad to get a closer feel. I don't think your stirrups are too short, I think you just need to sink your weight through your heels. Not pushing, but let the energy flow through your legs and down your heels, not your toes or the flat of your foot. Right now you are in a chair-seated position. Bring your legs back a bit and I think once you practice riding with no stirrups for a while and the concentrate on keep your heels down, that might solve the problem. The problem with chair-seated riders is that that they aren't really using their legs for anything, hence the heels up. If they are doing anything with their legs, they've usually got a pretty hard grip on the horse that is just tensing up their legs and not helping their position.
I hope that helps! :)
Opportunity is missed by most people because it is dressed in overalls and looks like work. ~Thomas Edison