Now that I think about it, red doesn't do much for me either. Odd.
Pink is my favorite color, so I tend to gravitate towards pink things, but I also like a variety, so I will often choose colors that I don't already have first, unless the toy is a very striking shade of pink (for me, that usually means day-glow). I'm also a sucker for swirly marbled silicone. That looks awesome in any color.
Its so strange to me that I've been going for pink toys for the last year. I'm a rainbow girl but several shades of pink and red (I try to avoid purple if possible but still have pinky purple) look so nice like the many colours of our lalas lol