Hi Nasayag ! they look pretty good to me. I am just an amature so dont take my comment as the exact thing to do. A 30 seconds or even 60 seconds gesture drawings are usualy done to warm up your hand before you go into the drawing you want to do. Just so you get your brain to feel that motion, energy or flow of the poses and be ready when you do a drawing (not a sketch). So i think your gestures are good and even the proportions are good. You are on the right track in my opinion. Practice, practice, practice and never be discouraged is the only options we have.
