So after playing with @RoverDude's Otter Submarine mod (which you should definitely check out if you haven't) for a while, I noticed a few things. One: It's very fun to drive a sub all over Kerbin, and two: that the stock underwater effects are extremely unaccomodating. Not only is it impossible to see the sea floor beyond a certain depth, and the surface of the water at all, but the fog does little to create an illusion of depth, with it's ridiculous lighting effects which look more like the souposphere of pre-0.90 than water. In short, while the mod is extremely fun to play with the way stock handles being underwater, while obviously far better than olden days, is still terribad. In short, what I would like to ask is whether or not it is feasible to ovveride the stock Water System with a better one. I believe @Fengist was working of something of the sort before he left the forums, but I haven't a clue about the specifics of it.
Screenshots for emphasis: