Deconstruction: Leather has a lot of things to say about Comic Book Tropes, especially those concerning Superheroes. Inverted in the last two chapters when the Super Hero Darkhood refutes pretty much everything she says, making the story a Deconstruction of supervillain motivations.
Darkhood: We don't need villains to be heroes... but some villains? like her? They need us to need them.
Some of the parts that don't relate to those motivations still make for a good deconstruction of the rest of the genre.
Dude, Where's My Respect? and Dude, Where's My Reward?: Leather seems disgusted that, while villains constantly make the Front Page of every newspaper around, heroes are lucky to get onto page four of the local press and struggle to pay off the bills.
Leather attaches one of these to Todd's neck on a couple occasions to keep him from running to the police. It is later revealed that it's actually a fake, with Silly Putty instead of explosives.
In Trey, Mr. River mentions that Jack O'Knaves will implant explosives in people like himself who would otherwise want to escape Jack's service. Shortly thereafter, Todd discovers that he himself has been given one.
Redemption Equals Sex: Mocked. Leather regards this trope as sexist and insulting and has nasty things to say about wielders of redemptive genitalia.
Rogues Gallery: Discussed as a concept. Leather is very much a roving professional, very much a lifestyle for the hell of it. (Neatly matching up with her name, as it happens.) But there are also villains who fixate on one hero. Worse yet, they're regarded as a good deal less sane, and a LOT more dangerous. Interviewing Trey establishes that such villains are also sometimes seen as more pathetic, especially in the lower tiers.
Running Gag: In Interviewing Trey, Jack O'Knaves has two:
Cracking jokes about Chapman's environmental consciousness.
Misstating Leather's name.
Secret Identity Identity: Mild version. Leather thinks of herself as Leather and has discarded her old civilian identity.
Super Registration Act: The distinction between superheroes who work with the police and vigilante freelancers is noted
"Some heroes have sanction — they work with the police, they follow procedures, they file reports. Freelancers were vigilantes. Depending on the city, the cops might turn a blind eye to them, but technically they were breaking the law."
Stealth Hi/Bye: Jack O'Knaves pulls this after talking with Todd. As a stage magician, he naturally has a good disappearing act.
Weird Trade Union: Leather's henchmen are unionized. So are the outlaw teamsters who pack up, transport, and unpack all that cumbersome equipment you find in those constantly-being-relocated supervillain lairs. Yes. The supervillains have their own moving company. As well as their corporate affiliate, a temp agency for forensic technicians who specialize in removing evidence from crime scenes.
What You Are in the Dark: When she stopped one robber, Leather thought for a few moments, then took the money, paid off her bills, and decided on a life of villainy rather than virtue.