His arms a little late and there's two things I'd see that I would work on to fix it. First, let's look at the early pronation he has in his forearm at hand break. His thumb is pointing back towards centerfield at the bottom of his arm swing. Excessive pronation can add more stress to the arm and some argue that it also helps to cause timing issues, such as the the arm being late. I'd like to see his thumb pointed in the complete opposite direction, towards his back hip, when he breaks his hands. It'll help facilitate a smoother arm action and not cause him to pull up towards his shoulders in an inverted W pattern (for the record it doesn't look like he get's his elbows above his shoulders into a full on W, but it's not far off).
Second, and I think this is the biggest contributor to his late timing, is that he doesn't get his hips working down and out early in his windup. Instead, he comes to a balance point and then almost drops straight down before getting his momentum going towards the plate. This causes him to not get his hips moving ahead of his hands. He's not creating good separation and in turn he's rotating his upper half at the same time he rotates his lower half. He's probably losing out on some velocity by doing this as well as adding more stress to his arm.