In almost every exterior shot of Gotham it's snowing/raining in the middle of a thunderstorm, despite the fact that #937 very explicitly makes a point of the actual date being Wednesday, May 31st note Which would make the year 2017, which can be seen quite clearly on a computer monitor while Batman is exploring the Colony's base. At first, it comes off as artistic license, as it is cooler to see our heroes running around a Gotham City that is constantly ominous...but then you recall that the Batman: Rebirth one-shot featured Calendar Man's weather machine that changed the seasons on a whim. Bruce saved Gotham from dying, but maybe not from some crazy weather...
Batman's decision to hold Jacob Kane captive in the Belfry instead of turning him over to ARGUS or other proper authorities isn't just out of a desire for revenge, it also avoids the problem of the media getting wind of Jacob's involvement in the attack on Gotham and connecting him to both Bruce and Kate, and the resulting news firestorm that would create. Granted, there are other ways this could still happen, but not as easily.
Spoiler and Orphan's detailed knowledge of chemistry and plant pheremones seemingly appears out of nowhere when they need to figure out a way to cure the enraged Gothamites during "Night of the Monster Men", but that realization happens right after Batwoman reassures Batman that her team can handle themselves. Because it's what they trained them for. And that training apparently included advanced botany.
I imagine they were trained in advanced Botany because that is the MO of Poison Ivy. Also botany is important in many poisons and chemicals that may be used by Scarecrow and other villains.
The Belfry's round conference table features seats for each initial member, marked by their emblem. The brilliant part is found in the way the seats are arranged. Working clockwise from Batman, the order is: Batman, Red Robin, Orphan, Batwoman, Spoiler, Clayface. This means that each member is seated directly across from their closest counterpart on the team (the leaders, Batman and Batwoman; the younger, techier members, Red Robin and Spoiler; and the two biggest outsiders, Orphan and Clayface). This means that no matter which way the table is divided in half, each half will contain a member from each of those subsets, making it evenly distributed and more conducive for discussions. Given the "all are equal" symbolism of a round table, this is a thoughtful division.
Kate's regrown hair in the second arc isn't just a stylistic choice. It works as an Expository Hairstyle Change to show the passage of time between the first and second arcs (about a month), but also gives some information about Kate's character. It shows that she's comfortable with both butch and femme looks, but more importantly, it shows her mindset after the battle with the Colony. We don't know why she chose to have her hair shaved to begin with, but after seeing the way the Colony perverted military order, it's not a stretch at all to think that she does not want to be associated with them, not even visually. Hence, a less militaristic hairstyle.
Fridge Horror
As seen in Night of the Monster Men, the monster venom created by Hugo Strange transforms people into mindless beasts. But when Colony Prime injects himself with a controlled dose of it, he still transforms but remains capable of speech and rational thought. Meaning that there's now a highly-trained black-ops soldier in a twelve-foot-tall monster body running around out there.
