My WWL has a flotation collar on it.
I do not try and wedge my camera and strobes into small or sensitive places. If I'm really after macro then I use a 60mm macro lens. The CMC is only for occasional use.
And so does mine and the float collar makes the WWL even larger. And has no effect on out of water weight. Are you attaching to a strobe float arm or an additional arm attached between the handles? How does the WWL not impact the way the strobe arm positions and stability?
A sensitive place only becomes sensitive when a too large camera touches something that is sensitive. If the macro subjects you are interested in are in open areas great, mine generally are not. If you find the WWL attached to a float arm nonintrusive for your uses I am happy for you, I find such a large lens parked on the bayonet holder obtrusive and prone to damage, both itself and the sensitive areas many macro subjects hide.