1st off, I really like your stuff! Your portrait studies are fantastic! Haven't had a chance to look through your whole blog yet but have really enjoyed what I've seen
As for your most recent post:
For your gestures, I think it would probably help to work lighter while searching for your forms and maybe simplifying the forms down would also help eliminate some of the sketchiness, as you wouldn't have to worry about capturing the nuances of the anatomy right away. I don't think there is necessarily anything wrong with being sketchy with these studies at the moment but if you are looking to clean them up, then that's what helped me when I've done gesture drawings before.
As for the heads, the only thing that I can see is the eyes on the male figure on the left and then the far eye on the female on the right. The male's left eye is a bit bigger than the right eye, other than that I think its great!. Then the females far eye looks like it is almost pushing out of the eyelid, rather than being cradled by it. I think just adding a little more depth to show the upper eyelid wrapping over the eye ball will remedy it. Outside of that small detail I think you did great portraying that three quarter view and the added rotation. I've never been able to get that view right, but you've nailed it! Just awesome work!
Looking forward to seeing more of your stuff!! Keep up the good work!!