Hey, really like the posing and the pacing of this!
The bone rig is looking pretty nice, I did notice a couple of things though.
Your acromioclavicular (AC) joint is getting pulled apart in places.
You'll probably find this will give undesirable results particularly for the trapezius which attaches to both the scapula and the clavicle.
I'd just generally watch out for the heads of both the femur and the humerus, slipping out of their sockets. Also the wrist is moving away from the radius/ulna.