I think I'd feel weird about riding a white bike, since ghost bikes are white. Id feel like I'm next. I'm not real superstisious but I'd still prefer a yellow bike to white.
Speaking of next, two fatalities in my county in one week. One a roadie who was taking the lane, obviously the car at fault, but if you pedal along on a 65mph highway taking a lane and don't look back.....
The other a local homeless guy. I saw him riding twice in the weeks before he got squished and dragged. I saw the way he rode, and thought, "he's next". Sure enough he was. He was weaving all over between cars while running red lights, his head all bobbing along to his headphones.
I digress. In the desert, I love a white seat on a bike that will park outside a store or whatever. White vynil will get very hot, but a lycra cover on a seat is easy to make. Peel off the Vynil, and staple on lycra. Once you butt is on it, it doesn't matter what color, so just draping a jacket or shirt over the seat works too.
Black seat in the sun long enough, and yeowww!