Lines of Communication
It's the early 23rd century, and humanity has finally spread out to nearby stars—very, very slowly. A number of slower-than-light ships have departed Earth over the last couple centuries, but communication over such distances has been impossible, even leaving aside the near-constant state of warfare that has gripped the Solar system for decades.
Peace has finally taken hold on Earth and its intra-system colonies, when a mysterious (but human-built) FTL ship appears in orbit around Neptune. While that ship was lost to the crushing atmosphere, enough data was gathered to allow the gravity drive and its related technologies to be reverse-engineered. Five years later, a prototype ship is setting out the farflung colony worlds, and re-establish contact with humanity's home. But what will the crew find out there?