as I can see:
rounding off on the elbow
some dk background across his shoulders on both sides (place another layer of white below render to see)
but, you're definitely getting better - still work on the rounding. Since you're most likely using lasso to do your cuts (like me), try using the...
rounding on helmet's right side and other areas like jersey wrinkles need some work.
the thin line of hair that causes a darker color line on the edge of the arm -- trick is to clone the edges
transition of hand warmer to leg is off - plus thin line of bg on that same leg
right side of cut...