I am not new to drawing but I have had an art block and hiatus for 4-5 years. I just wanted to get back into drawing in general, and I am using this site to slowly learn how to do that. However, the first time I am doing timed referenced drawings, so I wanted to know if I am doing things right so far. I would say I strive to make my drawings "come to life," and I want my figures to look less stiff.
Your portrait here doesn't look too stiff, and also not too fluid, so a happy medium. The only areas that look a little choppy to me are the ones where the lines are thicker, for example around the thighs. It looks like the lines there are made up of a lot of short strokes, which can definitely make the lines rough, and harder to correct later on. (It's hard to tell on my small computer screen so please excuse me if I'm wrong!) In order to reduce the choppiness of the thicker lines, consider increasing the pressure with one large stroke along the thigh instead of drawing over the same areas in shorter strokes.
Overall, the form and proportions look fantastic, and accurate. You are capable of amazing art and realism!! I hope this was helpful input!
I've seen your Google Drives before, I feel that your drawings are obviously raw and energetic. I just totally love the range of expression, emotion, and movement in your 1 minute sketches.
However, if I was to make another improvement, then it would be to just please do 75 minutes of 30-second hand and foot poses? The reason why??? It's because if your current goal is to make your hands and feet less stiff and more fluid, then go right ahead. Cheers and pray for your health and safety, and I hope you find these completely and totally kind and encouranging. And if you wanna see more information, check out the Glenn Vilppu drawing manual, link here: Vilppu Drawing Manual