I really like your equitation for eventing. You know what I like about it??? I'm going to tell you!
For one, I really like that you're not laying on your horses neck. That seems to be a big thing right now. Everyone's doing it. Just hurling their chests onto their horses neck over the fence. I like that your butt is out of the saddle, but not sticking up in to the air. That also seems to be a big thing right now. I believe it has also been dubbed "Porno Butt". Yikes!
Your toe is turn out and i'd like to see your leg a weeeee bit more forward, but otherwise I like your leg and you look like a solid and confident rider.
As for your pony: I'd like to see him/her jumping with legs square and out in front of the chest, instead of underneath and uneven. But your horses expression is lovely and is being really quite brave over that wooden fence!
Overall, not bad at all. I would like to see you lower your hands a couple of inches onto the side of your horse's neck. This will allow you to give some rein and encourage your horse to stretch over the jump without interference.
You seat is very nice, but I would like to see your lower leg forward, at the girth. If that horse were to plow and quit in front of the jump, having that lower leg so far back will destabilize your position. You will topple forward big time.
I would also like to see you ride on the inside of your lower leg instead of on the back of your leg. Riding on the back of your leg like that will make it impossible to ever wear spurs, and they are a wonderful tool on XC. Also, having your toes sticking out so far at the upper levels, risks hooking your toe on a flag. This can really twist your ankle and injure it.
The horse looks like he may have jumped while pretty heavy on the forehand. If you had maintained better engagement of the haunch, he may have had a rounder, lighter form over that fence.
Funny you should say something about falling forward because of my lower leg. Not long after this picture was taken, I fell and broke my leg going over this exact same jump. Probably because I was tipping myself too far forward. I sure learned my lesson!