Awlgrip Oyster White is what I asked for...it looks like the newer version of Hatteras Off-White and is a standard color, so if it has to be matched, it is easier. I used Flag Blue for the bridge stripe, which isn't holding up too well, and Claret for the boot stripe, which honestly is too dark, but it's holding up well, so I am going to leave it as is. It is too much trouble to change it.
I don't know of any way to keep decks from getting hot in the sun, especially in the tropical latitudes many of us frequent. However, nonskid decks reflect less glare. Darker decks get even hotter, it seems to me. Even teak decks get pretty hot when they sit in the sun on hot days.
I used Oyster White on the decks, with their nonskid mixed in, and a flattening agent as well. I don't see a lot of glare off them. However (and this may be the key) I have noticed as I get older that I need sunglasses all the time when outdoors or I get headaches. Now I understand why I see all those old folks with opaque black glasses over their reading glasses- I'm going to be one of them in a few years

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If you look at old illustrations, the first Hatteras colors were actually kind of an eggshell or cream color- very much off-white. They brightened it up in the late eighties and early nineties. Now they use much cooler whites, which I am not sure is an improvement.
I like the look of dark-blue or black hulls a lot- very salty. But they do show dirt easily, and print-through, and it is a LOT hotter inside the boat. Make sure your AC works well if you have a dark-blue or black hull.