I wear very little black, but I have tended towards darker colors. I've found that using earth tones blends well, similar to a capsule wardrobe, and you can incorporate greens, blues, and khakis along with darker colors like navy and black. Darker shirt, lighter pants, or lighter shirt, darker pants, and rotate through. You don't need to have very many different colors to effectively dress differently every day of a week or even across two weeks.

Because of the need for minimalism in travel, my wardrobe does tend to be relatively conservative and muted, but it's not all-black all of the time. You can certainly have some color.