The story is a satisfying tale of finding some happiness in the walker ridden world. The Governor not only adopts and is adopted by a family, but it's a family with a girl, Megan, pretty much his own daughter's age, and the hugs they exchange, the new daughter in his arms, ripple back to the the Governor's life before the biters aka walkers took it all away.
The Governor also finds comfort with the woman of the house, Megan's young mother Lilly, reminiscent in some ways of Maggie. The episode ends with the Governor saving his new daughter from a walker attack, the night after he and Lilly make love. It's about as happy a family as we could get in this apocalyptic world.
But the happiness will have its boundaries, and not just from bumping into walkers. We know that it's close to time that the Governor will come into contact with our people in the prison, and what will happen then? Will the Governor plead for mercy and forgiveness, on behalf not so much for himself but his new family? Michonne and Rick would never accept him.
On the other hand, they would take his help, wouldn't they, to fend off a walker attack. And what would Hershel counsel? How far can forgiveness and redemption go in this world?
Whatever the result, the Governor's return is welcome - at least to the viewer - and signals a ratcheting up of all that will now happen in this season of The Walking Dead.
See also The Walking Dead 4.1: The New Plague ... The Walking Dead 4.2: The Baby and the Flu ... The Walking Dead 4.3: Death in Every Corner ... The Walking Dead 4.4: Hershel, Carl, and Maggie