I think that this sounds really great! The only change that I suggest is the end. Maybe consider ending with something like "Thank you for this opportunity and for your consideration. I wish only the best for this band and its future, which is why I believe I would be great for this position."
Answer:
-Because they like you. They see something in you that makes them want to be your friend.
-Your art reminds them of something they value.
-Your art makes them feel an emotion they want to feel more often.
-And lastly, you make art specifically for them.