Overall you look pretty good. But I would say that it appears to me that you lack momentum, you are unable to delay shoulder rotation and you open the shoulders a bit early. This leaves you in a position where you must throw with more arm. You might be able to increase your velocity slightly AND take some stress off the arm by improving this.
I think the first issue is you don't appear to get into an opposite and equal position at foot plant. Part of this issue is simply that your arms don't mirror each other. Your throwing arm extends back fairly straight but your glove arm remains bent. This means the glove arm is quicker than the throwing arm and by doing its thing quicker, it pulls the shoulders open early and steals the timing needed to delay shoulder rotation. So, part of the fix is to extend the glove arm to match the throwing arm. Do not change the throwing arm.
The other part of this issue is that your glove arm starts to drop early and that also leads to opening the shoulders early. Ideally, you want the glove arm to take the same amount of time to do its thing as does the throwing arm. That starts with getting into an opposite and equal position at foot plant.
The second issue is that you really don't start building significant forward momentum until after the peak of your knee lift. You need to get moving forward sooner and faster. By not doing so, you inject more time into your delivery and that's time for things to go wrong (like dropping the glove, opening early, etc.). Plus, it makes it harder to delay shoulder rotation because everything gets drawn out timewise. Getting the hips moving forward sooner and faster will eliminate unnecessary time from your delivery and it will adjust your timing so that the front arm doesn't have to take significantly more time to do its thing. In other words, it will be easier to be in the opposite and equal position at foot plant.