The plot has been paper thin the entire last half of this final season -- and really, for several seasons.
It's almost like the show is split down the middle. The first 3-4 seasons it was fantastic, and arguably as good if not better than TWD. Over the next four, they "killed" the main character off-screen [she was basically just "gone" when the show resumed, and presumed dead until the 2nd to last season], and replaced her with a character from TWD, who I think they expected to carry over a lot of viewer eyes. Instead, the show became more and more absurd.
And really, as each season got increasingly less coherent and further away from what made the how initially compelling, the bad plots blur together. For example...
-- There was the season where they all become truckers.
-- Then a season where they all became cowboys.
-- Then a season where they all were rolling around in radiation suits, as were all of their enemies
-- Then a season where Strand became a tyrant in a tower, and all the others banded together to fight him
Ultimately, the writers decided to end the season on a generally happy note. Strand apparently has turned over a new leaf. Daniel reunited with Luciana. Madison sacrificed herself for the others and gave them hope... only to inexplicably cheat death a second time. Alicia returned -- similarly, from the dead -- and had a 5 minute cameo to close out the series.
But the road to get to this semi-sweet ending was built upon so much sloppy writing, goofy plots, and deus ex machina that it's hard to take any of it seriously as a viewer.
If nothing else, the ending gave the core nucleus of the show -- the quartet of characters [Madison, Alicia, Strand, and Daniel] who'd been around from the 1st / 2nd episode of season one -- a nice, happy send off. Mean things were said amongst this group, then rescinded. The original characters had a chance to say goodbye to one another, and go their separate ways on good terms. And Madison got her daughter, who ostensibly died at the end of last season when the actress decided to leave the show, back from the dead.
I'll always remember that the show started out really compelling, but I'm happy it's over. Hard to believe that it dragged on as long as it did, quite frankly.