Sleeve and armhole for Classic Shirt

Can you offer some advice? Photos are of muslin with sleeve basted in. I started with Size 6 D cup and graded to Size 10/12 at hips. Because my upper arms are heavy, I made a 1/2" wide arm adjustment to the sleeves and used size 10 for sleeve. First question- are the shoulders too broad? Then the sleeve is clearly not yet well sewn - but it seems a bit twisted toward the back. Any observations ? Advice?