I know i'm a little late because Christmas is already over but if they aren't painted yet, hot pink and bright green sound good-those are the colors of my bedroom! Anyways, whatever you do go BRIGHT because my barn had bright orange and bright pink and it looked really nice.
I have heard that they see blue VERY well, and in my experiences, I've been run out with at more blue jumps than other colors. (Maybe that's because I had this story in the back of my head?) But yes, as far as despooking, we've even gone so far as to put old Christmas trees under jumps when we were done with them to change it up a bit, lol