Looks great, nice work!

Nice! This is a great study. Good for you for coming back to it. There is always something to learn within anatomy. To deepen your understanding, you could study the connection points of the muscles, and how each muscle is layered. For example, the infraspinatus, teres minor, teres major, and long & medial head all connect to the humorous bone and interlace each other (shown in the full color image). The deltoid blankets all these connections, so it should be indicated that it is overlapping these muscles instead of sitting next to them (shown in the black and white image from Artistic Anatomy). Hope that helps. You're doing great!