I like the way you draw the head circle, the chest oval and the pelvic box first, at least that is how I see it, and build the figure from there. Some might say that there are too many repeated messy and dirty/not necessary lines, but I like that too. Maybe because it is similar to what I am also capable of drawing, however not so well as you. Overall your figures are believable and solid and beautiful in terms of lines and overall structure. I look forward to seeing more of your work.

One thing I noticed on most of these is that the ribcage and pelvis boxes are not deep enough/too flat. If you try to imagine a ribcage in those boxes you could notice that it would be way too squished. On a separate note, a couple things that helped me when drawing mannequins is actually finding the perspective of the environment that they would be in. I try to first establish a horizon line, the height of the whole figure (could just be a vertical line) and then drawing a box that represents the orientation of the figure, which forces you to find (roughly) the vanishing points. This way, you get the perspective of the whole figure and not each individual structure on its own. This will later enable you to draw that figure from a different angle by changing the perspective of the box. It's the way that Kim Jung Gi simplified his method and I personally learn a ton from practicing it, even if I want to unlive myself 2 hours in.