Hey zking, I took two of your drawings and drew over them to show you what gesture and mannequinization should look like. I want to be blunt with you- there is no time limit on learning these skills. It takes years to be skilled in being an artist. You don't just learn about these basics and move on, you will do them for as long as you are an artist. So, try to be at least close to the ability you see in my drawings or the drawings of other artists on this site before you try to move on to things that are going to be harder, and require the skills you learn in these basics. I hope this is helpful :)

The drawings look good, but what I feel that is missing is the sense of form from you shapes that make the gestures look flat. Some of your boxes, in the third picture, of the shoulder are not converging to the same point. In the first picture the form of the hips and torso of some of your drawings forms show more circles rather then spheres. You have the details and proportions right. One way I suggest to do warm ups of 30 sec gestures with either lines, bean, or basic shapes to loosen up, and not worry too much of the details and try to incorporate more 3D shapes accurately show the form. When you move on to anatomy, even I have trouble with this, focusing on drawing the muscles in the right spots can make a drawing too stiff. When you are comfortable adding the shapes and contours over the basic shapes it makes it easier to apply the muscles.

I love the fact that your lines are not fluffy which means you have decent control over your lines. What is missing in your work is depth. that you can achieve by changing the line value and strength so to say. Also, draw live models as safely and as much as you can!! and try to start with big lines and capture the movement of your model. after a little exercise, you can study the book by Joseph Shepperd "Drawing the living figure" it has all kinds of poses of both male and female bodies and breaks down the muscles and bone landmarks. It really helps a lot. Also touching your body and finding the bones that make their way right under the skin is quite helpful. Good Luck!