I think with world building, it's important to create a sense of culture even if it is just a fantasy, and the best way to do that is to look at a real human culture and see what makes it cohesive.
Laini TaylorWar is all we've been taught, but there are other ways to live. We can find them, Akiva. We can invent them. This is the beginning, here." She touched his chest and felt a rush of love for the heart that moved his blood, for his smooth skin and his scars and his unsoldierly tenderness. She took his hand and pressed it to her breast and said, "We are the beginning.
Laini TaylorIn moments Akiva was up in the ether, scarcely feeling the sting of ice crystals in the thin air. He let his glamour fall away, and his wings were like sheets of fire sweeping the black of the heavens. He moved at speed, onward toward another human city to find another doorway bitter with the devil's magic, and after that another, until all bore the black handprint....Once all the doors were marked, the end would begin. And it would begin with fire.
Laini Taylor