I agree that maybe you should just do the bust. The legs/feet and arms/hands are really letting down at the moment, the proportions dont seem right, close but not right. the hands in particular seem really small. And as BrianP said, without the concept of the arms and lower body your going to be guessing that area and it…
honestly i think that you had the right idea of only doing a bust. also without concept for the lower body your are going to be focused on the design of it all rather than focused on raw sculpting. anyways, as for my crit i would say your shapes are very bloby right now. focus more on your big shapes first, clean those up…