For whatever reason, the flash-sideways are a type of resolution for these characters. Each character has one main regret in their life, and the off-island flashes are helping them to resolve these issues.
-For all of the vitirol (deserved and un) regarding Kate's plane in season 1, it represents her deepest regret. Her running and me-first nature got her childhood friend killed. So, in her flash-sideways, she takes the time out to Stop running and help a pregnant girl.
-Locke lets go of his "destiny" by tearing up Jack's business card. Old Locke would have called, scheduled an appointment and if the surgery didn't take, he would have wheeled himself outside of Jack's door banging on it yelling and crying. This Locke was more realistic.
-Jack got to deal with his father issues... not by talking to his father but by being a better father to a son that he somehow has. He supported his son even though he never received such support himself as a child.
-Sayid got to see Nadia happy, but recognizes that he himself does not deserve her for all of the evil that he has committed.
-Ben got to put Alex's welfare ahead of his own thirst for power.
It's not clear yet how these people have been given this opportunity but they seem to be getting a chance to do the correct thing and move on from their largest issues. It's very intriguing thus far and I'm curious to see how these two timelines eventually merge. I'm assuming that they will because I doubt that the writers would have these flash-sideways(ii?) not mean anything.
