For background activity, I was thinking of independent events such as a convoy jumps into (or out of) the system and docks at the station or pirates that mount a raid. In scenes where there are sufficient asteroids, we could have mining ships going about their business. Anything really that give the semblance of life to the Nexus Universe.
Although I get the concept that space is unimaginably large and you're not going to get lots life in one little area, sometimes Nexus just felt a little too sterile... there was just me and whatever I was sent there to kill