Your hair sounds gorgeous as it is but?
I would recommend soft tones of copper or toffee blonde. Given that your hair is layered I would ensure you have fine weaved sections to ensure you keep a soft natural look. ...More >
DO NOT be tempted to have them placed on the top sections around your parting otherwise you will always see the re growth coming through every 4-6 weeks.
Only have them applied 2" below your parting and the remaining hair below this. This will give you a beautiful natural effect that will last and prevent you from having to return to the salon for upkeep.