I dunno where it was heard, but the soulsociety royal house thing does make perfect sense. If most souls come from the material world, the souls originally native to soulsociety would be the ideal nobility. Plus, it makes sense that human souls can reproduce, otherwise soulsociety would be enormous from babies born there, plus souls from deaths in the material world.
I still want to know what Hell's like though. We've seen 3 worlds, SoulSociety, Hueco Mundo, and the Material world. the material world's neutral, SoulSociery's good, but technically Hueco mundo was always ment to be an enigma, not definitively evil(well, not pure evil anyhow...), the real evil side was always hell, for those who can't even be purified by Shinigami. Yet we've seen nothing other than the glimpse of the gate when Shrieker was beaten way back in something like episode 4. confused