One of the rejected nicknames for Chigs in the pilot? Walkers.
Given Vansen and Damphousse, it's apparent the Marines have opened combat jobs to women in the 'verse. As a side-effect of the War On Terror, in December 2015 Defense Secretary Ash Carter ordered all combat jobs opened to women starting in 2016, despite resistance from USMC General Joseph Dunford.
Nightmare Fuel: In one episode, the Chigs are testing a weapon that basically weaponizesNightmare Fuel. It causes your deepest fears to be cranked Up to Eleven. The only way the squad is able to escape is by marching in lockstep out of the weapon's area of effect. Through a minefield. It helps them overcome their fears because they trust each other that much.
Retroactive Recognition: James Morrison, who plays Tyrus Cassius "T. C." McQueen, is likely far more recognizable nowadays as Bill Buchanan of 24 fame.
Uncanny Valley: Between the bits of "skin" that have flaked off from lack of maintenance and the fact that they all have crosshairs in place of ordinary-looking irises and pupils (even theSex Botmodels) the Silicates invoke this trope pretty heavily.
What an Idiot: The human race. Created a slave race only to have it turn on you? The solution is not to create another slave race!Dumbasses.
Also, when an almost unstoppable alien enemy force finally decides to negotiate, you don't get all irrational and emotional, endangering the talks. And you especially don't allow the negotiator to get killed. Geesh...
Even more so when said negotiator outright tells you they know all about your "war ending" battle plan and only entered into talks because it might damage their holy breeding grounds.