Go with the Olive Drab because that's what it's suppost to be and durning the WWII the OD paint never matched because of manufacture of the paint, how and what the paint was thinned with in the field, how much time it's been in the sun, and just about anything else.
If you think your OD is to dark you could always try a different brand of paint. I have found a differance in color between Model Masters and Tamiya, or you could just add a little white or yellow to lighten the color you have.
When working with WWII OD the only right color is the one your happy with.