I don't know if anyone here has made this point BUT if there was an offline mode the save files would have to be local, thus disallowing you from ever taking that character online.
This also means that the universe online would be separate from your universe entirely (As in 3 years when everything has changed entirely, yours would be the same (or changed as much as ONE player could impact it)).
Trade routes would be mostly static and not effected by players.
Basically, the entire game would be the same experience from when you started your save to forever. It's not as simple as creating a Offline Mode.
This also means that the universe online would be separate from your universe entirely (As in 3 years when everything has changed entirely, yours would be the same (or changed as much as ONE player could impact it)).
Trade routes would be mostly static and not effected by players.
Basically, the entire game would be the same experience from when you started your save to forever. It's not as simple as creating a Offline Mode.