I don't know if I'd place sea scintillation at 0, since the disturbances are caused mostly by atmospheric turbulance. You'll always notice more of a difference when the objects are low on the horizon and less as they move higher in the sky. The presence of moisture in the air will also add some degree to the refraction of light.
BTW, if anyone is interested in a cool (FREE) space simulation program that allows you to travel (seamlessly) through the universe, check out
Celestia.
http://www.shatters.net/celestia/
I did, however, forget how many stars are visible when there's no light pollution. I only saw the Milky Way galaxy for the first time in 1996, when I moved into the mountains, away from the city. Now, somehow, I'm back near the city again. Oh yeah, it's called a "wife".