It was about time the writers gave us a Broyles-centric episode, he is such a mysterious and fascinating character and yet, one and a half seasons afterwards, we practically know nothing about him (apart from the fact that there is a love interest between him and Nina Sharp). So in this episode we find out he hides a sensitive man beneath the harsh exterior, one who has had his family deprived of him due to his excessive dedication to his job. Standing at the gateway between two worlds requires a lot of time and effort, and it cost Broyles his family. Another pleasant surprise is that he cares about his cases, as he obviously did about the Russian cosmonaut and his brother. However, his personal feelings don't get in the way of him doing what is necessary, as we witnessed first hand when he shot the cosmonaut.
Walter, Olivia, Peter and Astrid played a more or less decorative role in this episode, which was something I would've preferred done differently. There have been moments of chemistry between Olivia and Broyles in the past, where it was clear he admired her abilities and dedication, and she admired his leadership, trusted him and viewed him as an ally. This case and Broyles' sharing the details with Olivia could've been used as a vehicle for further development of their relationship.
Another thing that disappointed me was that Walter didn't have the time to properly solve the case, I so look forward to the final scene where he gives the explanations in each episode(gotta love Walter, he's amazing), and in this one it was cut short by the CIA's intervention. I do understand however that it was necessary for the plot, the Fringe division was operating outside its jurisdiction in this case and it was a matter of time before their access was cut off. The final scene with Broyles and the CIA agent was great, very atmospheric and threatening, reminded me of the golden times of the X Files (I sure miss those times). Fringe can certainly pull off the atmosphere, which isn't easy to do. After this episode there's legitimate reason to hope that the CIA and whatever subplots it may bring to the main arc will be more involved in Fringe's future cases.