First, you've probably all heard my prediction for how it will end, and there's not much to say on that that I haven't already. In a nutshell: There is no way this has a good ending, and Sam and Dean know it already. They'd have better odds against Sephiroth if he existed in their universe.
Second, even if my prediction is wrong, it's still probably going to take a whole year to finish the season with multiple month hiatuses at multiple points in the season. One in winter, and one in spring. There'll probably be a full summer hiatus about the whole season between the last two episodes.
I'll still keep track of it to update List of Deaths Wiki coz nopony else does, but I'm not going to "wait" for the final episode anymore, because that's just what the writers want. They're doing this to torture their most loyal fans, because torturing their fictional protagonists Sam and Dean isn't enough to satisfy their "interest" in that.
I'll just ignore everything past Nick's death and headcanon my own simple alternate ending to tie up the loose ends.