I want Cas to be God!Cas for a few episodes. I don’t want it to get overdone like Robo!Sam, but I want there to be a reason behind the madness. If Castiel loses those souls too quickly, then what was the point of him absorbing all of those souls?
Not to mention that this is going to be a lesson not only for Dean but Sam and Bobby too. All three of them kind of used and brushed off Castiel during season six in various ways (albeit Dean used and abused the most), so to have them realize the consequences would be a good thing for all of their characterizations.
All I ask is that in the end, this God!Cas development isn’t something that’s going to go to waste and I hope that it’s not something that’s going to get overused. I mean if you consider that 2014 shown in “The End” (season four) is still in some form possible, Castiel had to become permanently human, so how better than to give him a test of true power and then make him fall so very far like a good fortune play. However, unlike a fortune play, hopefully post-nuclear!human!Castiel will be better off than season four!angel!Castiel.