You have a good start, just need a bit of practice. These are the things that I noticed right off the bat for all 3 of your photos. They are underexposed and out of focus, but this is a common mistake and easily fixable.
In regards to your question of tracking or setting up camera to the jump and taking your photo at that point. I suggest until you get really comfortable and consistent at taking tack sharp photos and getting the results you want I would stick with panning. It is much easier and your camera does have a good tracking ability.
1st Photo your angle is perfect and great timing in the jump. The horse looks happy, the rider's face isn't too shadowed out. But leaving a bit of room in front of your horse is much more appealing to the eye. Remember the rule of thirds. Leave some room for your horse to move into. Other than that I think this photo was very well done.
2nd photo does have good timing but there are a lot of not so appealing distractions such as the gate to the right and the jump post cutting off part of the horse's face. Positioning yourself a bit more would have avoided this. And again leave some room for the horse to jump into.
3rd photo is much like the 1st. Good angle, good timing. I would next time though go with a smaller DOF to blur out those tents that are distracting my eye fromt he horse.
I want to say again that you do have a good start and are capturing the good moment, just be sure to pay attention to the whole photo, not just the horse. Can't wait to see more.