I have never really liked the heaven storylines on the show. You can tell that angels were an added concept and they writer's made am initial mistake of having angels too powerful. Because of that the writers had to contrive a lot of different ways to keep the Winchester meaningfully involved in those plots-largely involving Cas. The result have been mixed, creaky. But season 8 really goes a long way to correct this and the writers really strove to have a logical and grand angel story, for once. This episode sets in motion a lot of the best parts of the season-human!Cas, human!Crowley etc.-and it is a good place to start. I even like Zeke as a side character and the script is tight enough to give him a solid characterization.
Unfortunately, the writers decided to-once again-have one brother lie to other and have a secret. This has happened as a big central tension of an arch in seasons 4, 6, 1. It is a repeated as a minor subplot in most of the other seasons as well. The usage in this episode-and throughout the season-feels tired. It's not per se but we have seen this story before.