The last works very well for me. The school of fish is nice too. I would have to say that most will look better in color simply because oceanic color is unique color, color you do not see as often in land creatures. It is otherworldly to us, mysterious, and therefore, visually interesting.
I have to agree and would love to see these in colour.
I don't know, what to admire more: you as a photographer or you as a diver. That's damn good underwater work, regardless color or b&w.
I looked at both your color and black & white photo's and they are awesome. Something about black and white photo's that make them stand out, they get me every time. I admire your ability to take such beautiful photo's and your bravery for going into the ocean.