Say, Smiller, that's the most marvelous display of a portfolio of the figure drawings and sketches. Greatest of jobs so far, so greatest, on your quick sketches and figure rendering.
Well, in general, you're making some greatest progress for the first time from you. So, my issue with what I'm seeing specifically, is that the quick sketches have a bit too much extraneous lines. Would you kindly be a bit more boldest with your gestural lines, a lot more loosest with 30 minutes of 29 second quick sketches of figures? (1800/29=62 quickest scribbly pose warm-ups)
The reasoning why you should do this suggestion is because, to help make your lines the smoothest, slickest, and have the nicest appeal to the lines, and to make your lines of action and rhythm the least stiffest and the most dynamic, lively and spontaneous.
For more inspiration, here's an image for you to download and study.
It's of a Mickey Mouse ruff animation sketch done by Legendary Disney Animator, Fred Moore, for an unfinished cartoon, Pigskin Pluto.
Cheers and I hope these've helped.