i wouldnt go with blue, because I always get pissed when things are like, a shade off. probably just me though. id try some tan pants. or, if they exist, american flag print.
I was the same way till I bought white pants. As long as you're careful when you're not on the hill and you wash them from time to time, they'll stay pretty damn white.
purple, im not too sure how it would look, but blue + red = purple, so who knows maybe it could look sick. but i personally would wear white or red with that.