Too many rules that are based on what some XO thinks his skipper wants. If they issue 'em to you and there isn't any written guidance, wear what you want. Tan in sandy places, sure, but tan in Key West makes sense too because its freakin' hot there, and the lighter color is somewhat cooler. Basing your color on the your location can be kinda dumb at times. Are you trying to hide from the SAR helo in Fallon if you need a lift?
What is a pet peeve though, and you NUW guys (P-3 and exped EA6B) can answer for this... The floppy "boonie" hat with the desert flight suit is GAAAAAAAAAAAAY. Let me spell that out, gee, ay, why... GAY. Get a command ball cap or a piss cutter, but the floppy hat looks sloppy - like you're heading for the "crick" to go fishing. Don't need to hear about how its issued, lots of things are issued, that one needs to go - at least at home.