I'm not great with colors myself, and tend to favor earth tones, greys and black.
As to aquariums though, I never really liked the look of a really light/white substrate. I like the black substrates (flourite black, black beauty, etc.), or the brownish/mixed substrates (natural river gravel, flourite, etc.).
I think the white substrates I've seen tend to both show dirt and give the tank a washed-out appearance, whereas I feel the darker substrates tend to make the fish and plants stand out more.
There are some people who really like the look of white substrates (some of the pool filter sands are pretty whitish/light colored), and I have seen some tanks set up like that that actually look pretty nice.