City of Titans contains examples of the following tropes:
Bad-Guy Bar: The Opal Room, a fancy-ish club owned by a mutant with luck manipulation powers named Opal Palinski. It's considered neutral territory by most of the criminal underworld so rival villain factions often use it as a place to conduct business. This is not just enforced by Opal and her powers, but also by various faction leaders who see such neutral ground as a valuable asset.
Cyber Punk: The ePunk Radicals group fits this trope, being cybernetically enhanced hackers. The Black Roses fit this trope to a certain degree with their cybernetic augments although they are far from punks.
Good-Guy Bar: The Orbit Room, a revolving restaurant owned by a retired Silver Age superhero named Captain Orbit. It's a popular hangout not just for younger heroes, but ordinary citizens as well. While retired, Captain Orbit apparently likes to try to remain "in the game" by giving advice to younger heroes and it is implied he will be a mission contact.
Hero Does Public Service: Titan City has a lot of heroes that do this. Considering how it's a city famous for superhumans and their antics, this isn't surprising.
Hero with Bad Publicity: So far a young tech hero named Topaz has fallen prey to this, being framed by the Black Roses for the death of a undercover police officer. He is fighting against it despite being in a really bad spot.
Made even worse in recent updates as The Tarot, a group of villains that are known for killing heroes and breaking their employers out of prison were called in to frame him even further on his trial no less...
The game's title is one to Titan Network, a prominent group of COH fansites, where the project was originally founded.
There is a very prominent hero team named The Paragons,
Chaser drugs sound similar to Superdyne which was used by members of the Trolls gang, and Excelsior which was used by members of the Freakshow gang. On top of that the cartel for this drug is being run by a mafia like group (The Black Roses) just like The Family running the drug business behind Superdyne....
The Atlas 33, a superhuman team of both heroes and villains, held the line against a twisted villain named Cumulus Rex whom was using Hurricane Atlas to tear apart Titan City in 1998. Atlas 33 is a reference to the final hours of City of Heroes where many Player Characters did a stake out across 33 instances of Atlas Park.
Recently there has been unveiled group that is simply named The Regency. The Regency seems to be somewhat inspired by the Circle of Thorns backstory wise.
Super Serum: Chasers are a highly addictive drug that gives the abuser fire powers. The first appearance of this drug was when a esteemed football player decided to use it with the assumption that it would improve his performance. Instead he ended up nearly incinerating an opposing player which created a scandal for Titan City, getting him vilified by the media, and getting his football career destroyed. He ended up becoming Skullcharred, leader of The Pyrebands gang whom all routinely abuse this drug.
The Mafia: The Black Rose gang is a cybernetically enhanced group of this.
Unconventional Alignment: Instead of the standard Good vs. Evil or Order vs. Chaos alignment system many other games have used, this game intends to use a three axis alignment system based on (Non-Combat)Violence, Honor and Lawfulness with some choices made during missions effecting one or several of these at once. To a certain degree, where you fall on any of these don't effect whether you're a hero or a villain since that will be more up to the player, but it will effect how NPCs react to you.