I can't think of a single naturally blonde person in my immediate family. All of us have what ranges from dark to light chestnut hair. I love the color of chestnut hair because it has so much more color than just plain brown hair.
My hair is a lighter chestnut color and it really lightens up in the summer when I spend time outside in the sun.
The only disadvantage I have found to having darker colored hair is that the gray hairs are more pronounced. The lighter your hair color, the easier it is to hide some of the gray hairs. With darker colored hair, they are much harder to hide unless you start coloring your hair.