I make this comment a lot, but it is of course one of the hardest bits to get right......
I doubt the hull is the same shape over the entire length, so that hull shading is most likely a bit off
I am certain of it that there should be changes to skeg (the shape indicates one, and I doubt it is angled more then 45 degrees with the waterline), bow (not the same over the entire length) and stern (aft of the propellers the hull is clearly angled down, but only the lower part is shaded).
other then that, really nice work!