Ok, you want responses, (and remember, you are in the RESTORATION forum). I'd keep it the same color (which looks beautiful if you ask me) and I'd leave the paint original without any extra metal flake or anything else.

Simple reasons:

It will look great stock and fresh.

Leaving the original paint color won't negatively affect the cars value.

Modifying a factory color is not much different than changing it to an entirely different color, just as expensive to correct down the road should someone buy it and want to go back to original.