Personally, I don't think there's enough contrast in the photos for a black & white image to be effective. Colour shots are the way to go and that third shot is great! Nice work.
I really like the third pic too. Is it a blend of different exposures? (To keep the ferns in the foreground sharp while catching the water movement?) Or was there just absolutely no wind?
Its a sheltered valley and was taken not long before sunset single shot - i'm really trying to limit multi exposure stuff/massive PP to shots that really need it