Hmmm, how do you determine the direction of the universe of where a void is?
To my understanding, voids appear to correlate with the observed temperature of the CMB because of the Sachs–Wolfe effect. Colder regions correlate with voids and hotter regions correlate with filaments because of gravitational redshifting. What if galaxies and matter follow a gravitational path much like a meandering river follows the easiest path (in this case, the warmer path of sorts)? I'm no cosmologist or astrophysicist, just a curious mind.