One this that is kind of funny is how complicated the whole plot to get Culber back is. When Colber was dying/dead, his DNA/conciousness was uploaded into the mycelium network when Stamets embraced him due to Stamets still being connected to the network at the time. A spore attached itself to Tilly after the Discovery was using the mycelium network in the mirror universe. The spore on Tilly grew into a duplicate of her high school friend, May, and created a cocoon to bring Tilly into the network because it was afraid of Culber which was seen as a threat to the network. Then, when Stamets and Michael go into the network to save Tilly by partially jumping, they find and save Culber and Tilly but only by May sacrificing the cocoon and connection to the Discovery.
Season one was very predictable in fan circles, but I feel like no one would have predicted these events lol. The most we knew was that it had to do with the network and the spore on Tilly.
The story really didn't have set up though. S1 at least had that, the problem is it was done badly and predictably. Here it was just "Oh btw this happened to Tilly during part of last season, and this happened to the doc" and ran from there.