I just wanted to say, there is no reason why you should restrict the beguiler class to 6 spheres. Spherecasters in general have access to all spheres (regardless of casting tradition; i.e. wizards and sorcerers can grab the Life sphere, druids can grab the Illusion sphere, etc), whereas the individual spherecaster rarely invests in more than 3 spheres. If you want to personally limit yourself to those 6 spheres that is fine, but it shouldn't be a hard limit on the class itself.