Tracing is a good tool to get your hand used to making the right shapes, and can help some with accuracy. You'll want to use a variety of practice tools to improve at art overall, like adding in drawings of different lengths and subjects.
Don't be discouraged. Drawing is a skill that takes time to learn, and anatomy is especially complicated and difficult to study. Focus on the process of learning and practicing often instead of worrying about results. Even the masters have bad drawings in their sketchbooks. The results you want will come with time.
Your anatomical breakdown looks solid. Keep at it :)
You're doing really well capturing the motion, simplifying shapes, and making readable poses for 30 sec drawings. Keep up the practice! Your lines are confident and the poses are interesting.
I think if you practice making slow, deliberate lines in longer drawings it would help you get more refined lineart, and less retracing.
Keep up the good work! :)
