I am English and i've been riding for around 10 years now.
Your overall position is ok, and your leg position is very good, but if you want to avoid falls you need to sit up much straighter.
When I was taught how to ride, As I got better I started to ride much younger and less in experienced horses, so I had to be prepared for the worse, I kept falling off at refusals and run outs and my instructor told me to sit right up with a much shorter rein so that I was ready for anything, and only to fold and stretch at the last minute, then straight away sit up tall after the jump riding the horse on. And also when you jumped the double combination the bounce in between seemed a bit tight, if you make it a little bit wider your horse has to stretch a lot more which is good for it's muscles.
Keep up the good work, your riding is great! x