I already said this in response to another post, but I feel so strongly about it that I am putting it in a post of its own.
I’ve seen people complaining that Cas shouldn’t trust Hannah because she asked him to kill Dean, but we’ve already had development past that point in the narrative, and I’m not sure why people are ignoring it. In the season finale, Cas spoke with Hannah honestly about what he thought and was trying to do, and he also listened to and acknowledged the reasons she felt she couldn’t trust him. She realized that she had been WRONG.
Hannah had no idea what she was asking when she wanted Cas to kill Dean. And it’s not just that she was testing Cas, though she was. Disturbingly convincing information had come to light that seemed to indicate that Cas was deceiving them all and sending them to their deaths— in that moment her fears and concerns were for her fellow angels. She was showing the first signs of her ability to grow into a leader. She thought she was asking for the punishment of an unreasonable and uncontrollable killer who had slaughtered a comrade in cold blood. She also thought she was asking for a punishment that she had been told her entire life was an acceptable way to punish someone.
Where Hannah ended the season was realizing that she had been wrong to doubt Cas’s goodness and intentions, but also seeing that she shouldn’t be afraid to question him or to assert her own beliefs. This is a crucial step on the path of Free Will, AND the path to being a leader of angels in heaven.
Hannah doesn’t have Cas’s great love of humanity (yes, he loves one human in particular, as well, but he DOES also love humanity in general) yet, but she is literally the first angel since Cas who seems to genuinely be developing an understanding of Free Will and the desire to use it. Hannah clearly cares about the state of heaven and wants to fix it. This is her arc for season 10. She needs to stop asking Cas to lead the angels (which he doesn’t want to do), and realize that SHE can lead the angels. She needs to realize how important it is to understand and care for humanity— that THAT is their sacred mission. She needs to take over the rule of a new & understanding heaven, and ask Cas only to be willing to share his wisdom and guidance with her, as someone who has more experience and understanding of humans and Free Will.
You guys— Cas is FINALLY going to successfully teach poetry to a fish!