Don't be so hard on yourself. Even if the proportions could be polished, you captured the likeness of the subject very well. I also like the cyan blue rim light he has on the nose altough the one on the shadow side should be more discreet. For the mouth, you could add some darker halftones in the interior to showcase more of the roundness of the lips and add a bright highlight to indicate the moisture of the lips. Good job.

Hello. The most important thing in this exercise is the flow of the rythms and these look like a success for me. For the feet, I usually just use the envelope shape of the whole foot and dont worry about the anatomy for this. You also used very few lines but captured the action of the pose very well. I still struggle with simplifying and add too much unnecessary information. Also usually in this step, you should use confident strokes with very light pressure since the goal is to add structure on top later with more defined lines. It's just an exercise so it's ok to use hard strokes, Just something to keep in mind. I think you did a good job with these.