Of your choices, I like red. It shows some dirt, but not like black, and it waxes out pretty good. If you do a metallic, it will also hide dents pretty good, as there won't be as many shadows.
I have always had a tough time keeping black vehicles clean and it was a lot of work to get the swirls out when I waxed them. I have had two black vehicles.
Light blue metallic seems to hide dirt and dents best.