The whole time-dilation thing has become a common trope in sci-fi, but this episode does it fairly well from a storytelling point of view. Science-wise, it doesn't make the slightest bit of sense and it changes the ratio of the time difference constantly, but that's okay. This turns out to be quite a sweet and emotional story by the end.
I was a bit let down at how lazy much of the writing was, though. The "alien" society are about as human as you can get, going as far as to mimic our history, social structure, beliefs, cultures, etc. Voyager seems very afraid of presenting anything truly different at times.