My castle in
Disneyland Paris has always been pink. I always thought the castle in Magic Kingdom looked a bit boring ;-)
I think it won't make a difference in the amount of brides who want to do castle pictures. I think for most, it's the castle that matters, not the color. For your color scheme, I don't think it'll matter much if you have a photoshoot outside of summer. Only during the summer season, during the morning hours meant for the photoshoots there will be enough light to show off the pink. I think if you have a shoot in Spring, Autumn or Winter what you will notice most are the lights.
In a year or so everyone is used to it.