I've wondered about this as well; but I was going the opposite way - with a denser charge field, you increase the opposition to solo gravity. If the earth's radius remained (relatively) stable, then more photons in the ambient field means more photons being emitted from the surface of the earth, thus negating more of the solo gravity field. I believe that this would help explain the gigantism in the fossil record that there is currently little biological explanation for. Perhaps an earth orbiting Saturn would provide this increased ambient field?