your chest is taking over the area where your shoulder should be. now unless you are going fro an armor effect. you still need to add more roundness to your shoulder. there are 4 target areas to the shoulder. the top. the front, the back, an the side.
the arms are both to short. if you look at yourself in the mirror you will notice that your elbows rest around the area of your belly button on a relax pose. your chars elbows are just below his pecks.
the biceps are to round. on a relax pose your biceps are almost an oval shape.
hope that gives you an idea on how to fix the arms, maybe if i can get a break i will sketch out what im talking about..