I'm kind of bummed there was no payoff with the Scranton Strangler. I didn't really need to find out someone from the show was the killer, but at least something. It's been talked about way too much to have no kind of payoff. Hell they could have had Toby just saying he was right or something throw away like that.
They did in some episode this season. Toby decides to visit the man who he thinks got wrongly convicted in jail, the next scene we see him walking out having been strangled, confirming it really was him. Its resolved.