Hey there, loving everything I've seen so far!! Your gestures are amazing, can't believe you can get that much down in such a short time! Your pen control is great and really neat lines!
For the cylinders and cylinders on body assignment looks like you decided to use ruler or line/curve tool to get everything nice and neat right? I like the way it looks but I think since your pen control is already great you can just draw freehand then everything will look more natural and not so rigid, just my two cents