What do you want to learn from each piece you do? You seem to be stagnating with your work, as every single piece gets the same criticism, yet you continue the workflow with the exact same steps. You won't get anywhere doing that.
I've said it before, but for your next piece you should:
start at a normal to small size like 150x150.
Neglect all signs of detail until you have been given the foundational pass of approval.
I know I'm a nag and not really skilled enough to give valid criticism, but I am observant enough to see what you need to do to begin to improve. You need to study fundamentals such as anatomy, start smaller. Remember ambition is not always in size. Challenge yourself to make the cleanest, sharpest, most pixel proficient small piece you can. Work slower. Don't go into detailing your piece until first you have established a foundation as has been stated many times, and think more artistically instead of technically. Give your pieces life, emotion, soul. You have it in you.