Probably the reason your friend made that suggestion is because most people can't see anything artistic about a brick wall. It was intended to make you think and expand your horizons regarding what you envision as your art.
In this shot the background is distracting, and doesn't add to the composition. If you intended the white balance to be skewed toward the blue, there ought to be a reason for it, whether obvious or stated. Yes there can be other elements in the composition, but they also should be there for a reason that people can understand.