Spn really fucked up by making angels knowable. yes give them human vessels for interacting with humans and for contrast with their true forms but also make them unfathomable. Make them manifest across landscapes, across the night sky. Let dean see cas in a crumpled trenchcoat faling asleep in the passenger seat but let dean be awestruck by castiel as an immense shadow flickering across distant mountaintops or in an uncanny assembly of clouds, dizzying and impossible but never evil, always watchful and warm. Let lucifer be something sam sees not only in dreams sneering from behind Jessica's face but as the shape the darkness takes on moonless nights and the sharp edges of his own shadow. Let the brothers feel increasingly uneasy and exposed as Zachariah watches them from flickering vacancy signs and motel tvs and telephone wires. We should be reminded that angels are not human, they are unbeholden to our laws of physics and the limitations of our senses.