Some consoles, particularly of the RPG variety, have included mini games for additional flavor.
How it could have meshed in the last game:
A bookie in the Rikti monkey Fight Club
A carnival style "don't let the ring touch to wire" game in the tech store.
A pinball machine for the sg base.
An old man to play chess against in the university.
The majority of the games here would work well ,and most are public domain. Pretty much any carnival game as well.
Obviously this could be used to add a great deal of flavor and environmental interaction.
It would add something to kill some time while a team/trial builds, or while waiting for your mates to log on.
It would be a fairly low investment of time and resources to include.
It could tie in with the mobile app features like the character creator, allowing us to engage in at least a small part of the world when we are away from the main game.
It could also function to remove a portion of the excess ingame currency, if you allow some sort of gambling functionality.Slot machine to get those wicked awesome boots. Skill game to unlock that weapon skin etc.
While I doubt this would be even remotely a priority I think it could add some depth to the world.