These look nice! but I think they're more of figure drawings than mannequizations. I think you're too focused on the contours and trying to draw the entire man than building him out of simple blocks and cylinders. More like a human shaped structure than an actual human. Remember that these are supposed to be a !simplified! foundation that you can draw a figure over, not a finished figure drawing. I hope this is helpful! Otherwise these are pretty good drawings and it looks like your making a lot of progress!

Not bad! The poses are clear. I think you're right about the line quality and I also think that your focusing a little too much on the contour rather than the larger pose. I would recommend removing the time limit and imposing a line limit, say 7. Then really, look at the pose and PLAN each line using a C, S or I line. When you have only 7 or so lines to describe a pose, you have to show larger portions of the body with each line which helps with the flow of the pose and the line quality in one exercise. I'm working on my line quality and this helped me make good progress, so I hope this helps! Looking good so far, keep it up!