SegaXtreme

Hi. I'm currently playing the first version of Phantasy Star Online. I don't have any way to hook it up to the internet, so i was just wondering if I am wasting my time playing the offline mode? I guess what I'm asking is is there an actual ending to this game that I can reach for or is it ongoing until all the missions are complete and then all I can do from then is walk around? Thank you!