I binged both seasons over the weekend and am quoting this because I found this storyline frustrating. We never see Brian communicate with anyone. It was hard for me to decide if he was just a sad kid with a disorder or Damien. It would have helped to have seen him talk to the therapist without his parents, or the social worker. I feel the same about Nancy, I character I ended up having sympathy for. There was a scene with her and Holden's GF in S1 where they talk about Brian and Nancy talks about being unsure if they're right for him and Debbie assures her that Brian is lucky to have them. It's one of the few scenes where Debbie doesn't come off as sarcastic and condescending.
Nancy's character would have been better served if we had seen her talk to anyone about Brian with anyone other than Bill. A friend, the therapist - the murdered child's family doesn't count. I was actually interested in the Bill/Nancy dynamic in S2 because I thought the push-pull was portrayed well. I love Bill and all, but his decision to leave over the holiday weekend was not the right one. Bill has an important job that he derives a lot of personal satisfaction from. He interacts with other adults and has other things to do than obsess over his child. Nancy apparently does not have these things and Bill, though not unsympathetic to her, is definitely brushing aside her concerns because he's either thinking about and/or exhausted by his job. It was fascinating to me to watch the unavoidable train wreck coming. I ended up being sympathetic towards Nancy because I could feel that she felt like a prisoner in the home, ostracized by everyone along with Brian, with her only adult companion leaving for days on the spur of the moment. Yes, that's his job and she's been through it, but circumstances are different after your minor child has been involved in a murder.
It is too bad about S3 because I'm interested in how the show would have handled it going forward.
I did think S2 was missing something because the team wasn't together as much. Of course the buddy road trips of S1 were great and I missed those. I wish we had seen more of Wendy interrogating the serial killers - I felt more badly for her when the boss basically told her that she had to step back from that than I did when her girlfriend told the ex-husband "no one important". There was a lot of good stuff to mine there with Wendy, a character I really liked, that wasn't done.
I think Holden is sympathetic to victims, maybe not as much as he is fascinated by the killers, but those feelings are there. He is easily frustrated with bureaucracy and just wants to get shit done, which is one of the reasons the boss wants Bill baby sitting him. I don't think the show did enough in S2 to show us Holden's "genius" - it seemed they were going for "he's the guy who knows the right questions to ask, but is a maverick in all other ways" but didn't quite get there. He's still very buttoned up in a lot of ways - he is actually ironing his tie in once scene and then during a stake out, takes it off but hangs it carefully over the mirror, even smoothing it out.
I did like the stake out montage - we got to see some fun being had with the characters though it conveyed the tediousness of it all very well.
I agree that interviews with the killers were really well done, well acted and tense. The actors playing Kemper, Berkowitz and Henley stood out for me, with Berkowitz's switch from hearing demon voices to admitting he didn't, particularly chilling.