Hey, I missed this post earlier, sorry!
I don't know if these qualify as in-depth discussion or critical engagement, but these are some videos/podcasts about BtS that I really enjoyed.
First up, Eurogamer has done a full Let's Play of the game which I found to be really enjoyable. They also had Zak Garriss, the lead writer from Deck Nine, on as a guest to play through the first episode again with them, which was also pretty fun. A link to the playlist for the Let's Play:
https://www.youtube.com/watch?v=XKNniUiE4bc&list=PLTZXfIDHhP2uQyhHzPiTdAa8QLt6yFarH
Next, if you wanted to hear the lead writer give a talk about what the writing process at Deck Nine is like, with a lot of examples of how they went about writing Before the Storm, here is a link to that:
https://www.youtube.com/watch?v=6HLx_kPNRGA
And finally, the crew at What's Good Games did spoilercasts for each episode, and here are the links to those:
Episode 1:
https://youtu.be/USgyjNu6URY
Episode 2:
https://youtu.be/t47w4CLLTtU?t=6948
Episode 3:
https://youtu.be/9TUMIiLpuBg?t=5170
These are just the ones that I have checked out, I'm sure there are others out there too, so if anyone else has any suggestions, keep them coming because I would also like to know!