As far as primals go, they are tied to Dalamud from the Meteor story. So Part fo the Meteor story is connected to the game's original storyline. The echo seems to be an ability we have never learned about, as far as how our characters have obtained that ability or why we have it. I'd like to know more about that myself.

In 2.0, they are keeping these NPCs, especially Minfilia, who is tied directly to the organization that connects you with a Path Companion. She also knows about your ability of the echo, so perhaps in 2.0 we should be getting some kind of continuation with that storyline.