I've been really enjoying Culber's journey this season. I don't know if it will dovetail with the main plot, but I'm optimistic they'll wrap it up.
I'm not sure I'm completely on board with the role Stamets is playing in it, though. He went through a spiritual experience of sorts in season one, so I'm surprised Culber doesn't feel like he can turn to him. Maybe Stamets is just too chill to provide the kind of support that Culber needs.