Maybe Season 2 is about a parallel story which starts at the same time as Lee's journey did. The new characters might cross paths with people from the comics or Season 1. And in the end they meet Omid, pregnant Christa and Clementine (if the two figures in the countryside are O&C) as a cliffhanger announcing Season 3.
Significant events in Season 1 that could be taken into Season 2 as déjà vues (to reward the players of the first season):
Shooting and screaming at the end of Episode 1, when Lee was looking along the street. And Glenn drove that way afterwards, so he might be in Season 2.
The girl who makes an appearance in the beginning Episode 3 luring the zombies out of the stores could've been a seperated member of the new group of survivors.
... (add more if you can think of more events that might have ran parallel)