Sonja Percy's address of Meredith Brody near the start, "Listen here, luscious locks", is perhaps a joking acknowledgment that Zoe McLellan had let her hair grow from her really severe short cut in Season 1 to a much longer style for Season 2.
Sic Semper Tyrannis is the phrase John Wilkes Booth said after he shot President Lincoln. It means "Thus Always to Tyrants." However, it's said that the phrase originated with Brutus and the assassination of Caesar.
First episode that features Daryl Mitchell and Shalita Grant in the opening sequence.
The M982 Excalibur is an interesting weapon, developed by Raytheon Missile Systems and BAE Systems AB. Wikipedia describes it as "a GPS and inertial-guided munition". It's a guided missile, but propelled by being fired from artillery, rather than carrying its own propellant. The OED defines a missile as "An object which is forcibly propelled at a target, either by hand or from a mechanical weapon", so LaSalle's description of it is perfectly correct. All artillery shells are missiles, but not all missiles are artillery shells: and some missiles are guided.
Agent Pride likes Chicory, a typical type of coffee found in New Orleans.