That freedom of creation is enticing, so long as it can grab and sustain players willing to feed each other new content. It's also going to be highly moddable, with scripting tools available to go so far as building your own jobs, objects, and maybe your own expansion. There will be a default spread of skin colors, sexualities, and other characteristics but you can tweak those yourself to create a world 'full of people who just fall in love with me,' or where other traits are predominant.
Humble talked about letting players get granular with the rules of their worlds, even.