I definitely agree with the previous posters who mentioned shortening the stirrups a hole or two. When sitting in the middle of your saddle with your foot out of the stirrup, the tread of the stirrup should bump your ankle bone or a little above. For someone used to riding Western, this is going to feel *really* short and uncomfortable. Once you get your stirrup the correct length, practice jumping position by bending both your knee and hip and squatting over your saddle, with your crotch over the middle of your saddle. When you get it right, you'll feel fairly secure and balanced, and that you don't have to lean on the neck. Novices assume jump position is a bigger adjustment or move than it is, it's actually pretty subtle - lift slightly out off the saddle, bend the knee and hip. The horse's motion does the rest. The third photo shows you demonstrating the best jump position.
Your long stirrup has put the grip in the back of your calf, rather than the flat of your calf, as other posters have mentioned. Second and third photo show the grip more correctly in the flat of your calf.
All that said, what I really like about these photos is that you and your horse appear relaxed, happy and like you're enjoying yourself. Your flat back and eyes securely up are admirable; traits lots of serious jumping riders struggle to develop that you seemed to have naturally.
Your release is quite good. In none of the photos are you interfering with your horse, and there's a nice slack or float to the reins in all of them. In the fourth photo, the release is a little too close to the withers for my taste and you can see you're sort of jumping up over your hands. Aim for approx. 1/2 way up the neck, with knuckles pressing into the muscle of the neck. Don't be shy about grabbing a piece of mane with one hand over the fence.
Your little horse is cute, willing and dead honest. In the first photo, she's showing quite respectable form, the others were not taken at the right moment to judge form. She's certainly safe and able, with a little work and polish she'd do well at small local shoes.
For a western rider and horse goofing around in the pasture for fun, I see some aptitude and some good qualities. How far you go with this really just depends on how seriously you want to pursue it.