If the subjective perspective is an illusion, an emergent behavior of a complex reality, then wouldn't we do better by trying to alter the reality (biochemistry and environment) directly than by abstractly influencing the illusion with notions of reward and punishment?
I see this as a false dichotomy. It's the old mind/body duality again. Your assertion about chemicals is not wrong, but you'll run into trouble if you act as if it negates the subjective perspective.