You know, the breakfast scene after the resurrection says a lot. Aslan, this immense lion, is romping and playing with the girls like a giant kitten. That contrast is vital. He's not just a war leader or a distant god. He's joyful, affectionate, and alive. The Witch is all cold calculation and sterile pride. The battle is, at its root, a contest between joy and misery, between abundance and scarcity, between life that celebrates and death that hoards. Aslan's playful, generous nature is as much a weapon against her as his claws. He's central because he offers an alternative way of being that is infinitely more attractive than her bleak rule.