First and Foremost - The Improvement is definately there!!!!! and it is much better than I can do.....
That being said, now for the critisim (all of it constructive)
On all of forms but the last two - the chin was WAY to large.
On the last picture, the space between the nose and the mouth was to large and the ears seem to be sitting to high on the head (of course commenting on Devil anatomy could get one into trouble)
Further, the arms are still two muscular (wish I had definition like that!!!!) - Again the fact that this is a Devil could explain that away.
The fingers appear to be too long (of course the nails could be giving that illusion)
Finally the feet look almost like an afterthought - no real detail there.......