There must be a 2nd in command to start taking action in the event James died. I suspect maybe we will get to see Sebastian Moran next season as he picks up where Moriarty left off, or at the least attempt to bring Watson down. Maybe it can even lead up to a similar story of Watson being saved by Sherlock (because we all know, Holmes is out there somewhere).

Um, that WAS the twist. Everyone assumed the mom was gonna be someone special or something like a time lord or what have you. So many theories about who she could be. But making her just a normal human was a twist I don't think many assumed.