For instance, one of my biggest pet peeves is someone having this extremely important person in their life that just suddenly materializes out of nothing. Taystee never mentioned Vee at all in the first season, never talked about looking for her when she got out (in fact, she stated that she was going to look for a cousin), never mentioned not being able to find her when she got back, never even mentioned someone similar in passing. Then we get an episode that shows Taystee's back story and, tada!, Vee is now in jail too! There really should've been more of a lead-up to that. It just felt like a really lazy way to introduce an integral character, particularly since she conveniently also had history with Red.
I also think the nun episode was one of the weakest of the season. They were obviously trying to go with a really shocking back story that we wouldn't see coming, but it instead just felt really artificial and out of character. There have never been any indications that she has any sort of fame, nor have we really seen any hints towards her desire for it. And they didn't really do that great of a job showcasing what put her on this path. It was like watching two completely different people.