I would say keep your natural hair color for the bottom half of your hair and dye the top red, I'd recommend leaving streaks of your natural hair color on top too, your natural hair color is gorgeous.
Bottom line, I think you should do a multi-dimensional red that incoporates coppers and golden blondes.
Since your hair is already light I'd say you should try doing it as a rinse or a henna so you can keep the damage risk as low as possible.