Really nice studies, I can feel the form in most(if not all) of them!
Keep it up!
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Hey, great stuff! Definitely keep it up. Is that all just from recently?
You mentioned stiff figures on another site (I'm Kaiser over there ), and I see what you mean easier here with the drawings themselves. Your method of blocking in the figures like ball-jointed dolls is something that can be helpful for trying to figure out how the limbs move and how the body is a whole, 3-d shape. But it stiffens up the whole pose. While you're busy drawing all those extra circles and lines, you're confining the pose into them.
Also, while you're spending time coming up with the joints and lines to connect them, it's time that you're taking your eyes off the subject and looking at your page. You want to try looking at your subject as much as possible. If you haven't ever had any courses on observational drawing, you might benefit from doing some practices to get you in the right mindset for observing. Blind Contours, drawing the subject upside down, etc.
I found a couple of youtube videos that might be relevant for you - this one more so with regard to how one approaches figure drawing at the start. here. (But this second one also kind of really quickly visually shows some gesture-drawing here.)