Highlights for chestnut colored hair

My natural Dark Brown hair color is dyed Chestnut(even though some think its black and/or red). I'm playing with the idea of highlights, but am not sure what color to use. I've had my hair Medium Brown with blond, carmel, and copper highlights before (not all at the same time). Any ideas or pictures would be much appreciated.

Thank you Juliana, both of those seem very interesting and helpful!