The options for toilet waste are flexible depending on your abilities to be open minded, and if you're REALLY proactive, you can even have a dry compost toilet. Wouldn't you sleep better at night knowing that ALL of your waste is being put to good use?
Earthships are completely custom designed, so the homeowner can decide how the interior and exterior will look. I'd imagine that anyone could take the basic philosophy behind Earthships and go in many directions. You could have a hobbit house or a Barcelona Pavilion . Personally, I'd like to build an Earthship that looks like the Wheatsheaf House. :D