You look great, especially considering you're just getting back into it!! And I love how you're smiling over the jumps. :) The tips I'm going to tell you will help you gain confidence as well as improve your riding. So here goes:
1. Heels down! Or more realistically, toes up. This will help keep you more stable.
2. Sit tall (full seat) and count your strides in. This will help your horse find the perfect takeoff spot and will give you a better feel for his motion. So either count (one, two, one, two
) in your head or sing a song with a steady beat (row, row, row your boat
) to help you stay in tune with his rhythm.
3. As you gain confidence, don't jump ahead! You're doing this ever so slightly in the second picture, and while it's not a huge deal it's best just not to fall into that habit in the first place. Don't get into your 2-point position before your horse takes off; let him come up to you.
4. Bring your seat a little closer to the saddle, open your hip angle, and bring your shoulders back. All this will help you be less hunched.
Good luck! And I'm not exaggerating... you look better than a lot of much more experienced riders I've seen jumping at that height.
Hope I was helpful!