If ***** and ****** had survived?

That1Guy

So, I've been wondering, had Walter and Sarita survived for longer, how would they have developed as characters? I mean, from what we had seen, they were really nice people who were being heavily affected by the apocalypse. Nick and Sarah weren't the only characters who were just kind of wasted this season, because these two also had some pretty good potential to become fairly memorable but instead they just died