I humbly ask the devs to look at my post as a possible idea.

1.Vehicles: The addition of this would be excellent for non flying, non speedster toons.
Champion online really did an incredible job with vehicles but I feel you can go futher with ie...
Super cars, hoover bikes, Hi tech Jets, space ships, Mechs and Creatures ie. dragons, beasts ;with customization features like colors and designs.

2. Never seen before powers like. ..stretching, shapeshifting & Increase or decrease in Size (Hank pym) .

3.Zones or possible instance for R/Ping only,imagine being able to toggle or click certain places, that sends players to a separate instance kinda like how beta instance work.
This allows gamers to R/P in peace from PvP and PvE kinda like a private chat room but I can see bases doing this as well.

4. Secret Identity : Imagine when players turn off the game their toon continues on in the world in their alter ID.
This Idea I saw in action at an MMO called Age of Wushu, its kinda funny to turn on the game see your toon either sleeping, working a job or hanging out in a safe public area of the city.
I'm thinking it could work similar to star wars old republic, on how you send toons out under your character to explorer or search for things even when you are'nt active.

4.Citizen of Titan City : COTC allows you to create your own cast of NPC characters connected to your character from the same create engine of COT.
I can see this being in the COT ingame store, 1st COTC character is free but rest you gotta buy character slots for if you want more.
As well you should be able to create a bio for them and have relationship section shown ie. ( sibling, parent, sidekick, spouse, romantic interests,
Side kick or child).
This way if another play engages them they know who created them

5.Archnemesis system: This allows players in their bio's to choose another player as a ingame rival.
If your a hero find another player who's a villain to build a rivalry and add each other to your rival section, similar to adding a person as a friend on facebook.
On your bio it will list all your archnemesis in your rogue gallery and vice a versa for your rival.
This isnt only cosmetic but you get updates and ingame detail on what your rival is up too, this also gives a choice if you want to foil their plans ingame.
If you are a villain and you want to troll your rival you can locate their COTC npc character and kidnap them for ransom or simply assault them.
If your NPC has been kidnapped you can track down your rival engage in a fight or sneak into their lair and take them back.
For villains they get Crooks of Titan City, same feature applies except for sidekick you can make them a henchmen, as they commit small petty crimes in your name, which sends the money into a villains account. or get nabbed by a hero.
If your villainous COTC gets nabbed by a hero just find the nearest precinct or jail and defeat the police then set him or her free out of prison.