First of all, very cute mare! I like her!
So for her, she looks happy and laid back (while yes a bit more impulsion would be nice if she's out of shape then she's probably going "butttttt I don't work anymore, who forgot to tell you?). I like happy horses so plus! She's got a trot I like and her canter looks like it'd be pretty nice to ride. If you're worried about her getting long and a bit strung out maybe try some Dressage? My mare's gotten tons better with her canter since I finally started working with my new trainer! Lovely jump, even being "lazy" she's got relatively nice knees. I don't necessarily see 'A' in this round but hey I'm also not really a Hunter so lets not take any of my comments on the horse TOO seriously!
As for you, you're position on the flat & over jumps look fine! Nice eq. "Chicken wings" yes but I know a lot of riders who do that and as long as you're releasing I'm not complaining. You could maybe stand to push your hips back more but honestly, not bad and I've seen a lottt worse. Focus on pushing down into your heels and letting the horse come up to you which should help keep yourself back and more centered, also if you're worried about getting ahead of her at take off spend some riding days on her just counting your strides until you get it perfect, then until you can't get it wrong? Not the most fun but it may help get you more focused on taking off with her not ahead of her! Love your leg, moved a little over the jump I could really see from the size but hell, that happens to a lot people (def. Happens to me so who am I to be talking?
). As for what you said about your release, some people like the crest release, some like the auto. I'm more of a fan of the auto release. As long as you're not ending up on your horses neck with your hands up to her ears it's a release and I didn't ever see you get your hands too far ahead! Your seat was nice and soft, wish you'd sit up more but that's all the Dressage lessons I've been having rumbling around in my brain. The more forwards you get, the more you close your hip angel putting your horse behind you. Open your hip angle and you push the horse in front of you, hunters likes you to be out of your tack and in a completely different seat though! Your hands also looked good but thumbs on top! Another one of those things I struggle with.
I hadn't seriously jumped in years before a few weeks ago and my "serious" jumping now is putting my baby over tiny little like 1ft fences as he introduce her to jumping. I did spent a lot of time as a barn manager at my old farm just watching hunter show after hunter show after hunter show.
This post is possibly (probably) a little jumbled, sorry 1 am and I should not be trying to critique people! But your horse is pretty, and your round looked fine. It did look like a rather small ring btw...