It's kinda hard to tell... I'd like to see the first picture with his head up, at a natural level to see how it sits on his withers. I'd also like to see a picture taken from the front of his shoulder to see how the tree points sit. I'd also like to see a picture of his back, with feet square, to get an idea of his shape without the saddle on. From these pictures, I'm wondering if the saddle is just a hair to wide in the front (the pommel looks like it might be ever so slightly too low, especially if these pictures are taken without being girthed up). The third picture makes me think the saddle's panels might be too flat for his back shape, but its hard to tell without a picture of his back without the saddle on. When you're sitting in the saddle, how many fingers can fit between the pommel and his withers? It doesn't look as though it would be pinching his spine through the gullet, but the back of the saddle panels may be putting too much pressure on his loins. I would try to get a saddle fitter out, or talk to Rick's Heritage Saddlery in PA, or Trumbull Mountain. They can help you take the right pictures and wither tracings, and give you a better assessment over email or the phone.
I've spent most of my life riding horses. The rest I've just wasted.