The biggest thing I noticed was the hands being too close to the saddle, and leaning forward. She looks like a great jumper! I don't think she is very consistent with her distances, though. I think the issue is just that you're leaning forward too much. Especially with a horse not trained to do jumping (just like my horse. He was trained western pleasure, so I had to turn him into an english and hunter jumper horse), they have a hard time feeling distances if you lean forward too much. It helped my horse a lot when I thought about sitting deep a little more, and bring my hands up. Not leaning back, because that will throw you off balance and you may get left behind, but if you just think about leaning back, you'll likely be perfectly fine. Just make sure you give a good release when you stop leaning forward!
She'd make a great jumper, and looks like she's very willing!
Riders aren't 16 and pregnant. Riders are 16 and arthritic.