the size of saddle looks acceptable, though just barely big enough for your very long femur (my jealous@) . you do ride in a chair seat. I think you might be doing that becuase of the downhill slope of either your horse, or your saddle balance, or both. I would like to see a photo of the sddle on the horse, as you tack it up, and maybe without a pad, and horse on flat ground. And, a photo of you in the saddle
in any case, your leg is out in front of you. you ride pretty nicely from your seat, but you'd ride even better if you had your leg under you for support, and it would help tremendously for jumping. if you could bring your leg more under you, then your knee would not be approaching the edge of the kneeroll.