It looks like a nice fit, however sometimes you just don't know until you put some mileage on it. Ask me how I know, lol! I swear I went through about 10 saddles before I found one to fit my Mustang well.
I would keep an eye on the saddle traveling forward as a possible result of the rigging position. I had that happen before because my horses have big bellies (my mare was a broodmare and my gelding is just plain chubby). So sometimes the cinch can travel forward to the highest point and takes the saddle with it pulling the saddle over their scapula area. Your horse doesn't have a big belly on him so that will hopefully not be a problem, but I just wanted to mention it because you mentioned either the pad or saddle traveling a bit on his back.
But it certainly looks like it could very well be a good fit for him.
PS. You will have to tell me if you find it comfortable. I had a Bighorn endurance saddle just like that and I felt like I was riding a fence rail. But the lady I sold it to loved it. So I guess it depends on your body and riding style.
Best of luck! I hope it works perfect for both of you.