Your studies aren't half bad :D I think you would really improve the rhythm in your drawings by drawing things that are constantly moving. As for anatomy, I think you could benefit a little more in regards to understanding form with a bit of Michael Hampton, you can find his pdfs online( you've probably heard this already haha) and I think you could look into a bit of Bammes' anatomy illustrations as well. Also for proportions of the human body, as long as you keep it in mind, you will eventually begin to "naturally" have a feel for the proportions of the human body. I think environments are "less interesting" because we as humans find a lot more interest in living creatures, I think haha. But I do agree environments are important to grasp. Just remember to keep perspective in mind when drawing environments, and just study from life. Other than that, just remember to keep doing drawings from your mind to test what you know, analyze your work to see what you have to improve on, and go from there.
Keep it up!