While I certainly don't think it's better than the S1 finale, it may be superior to S4 and 2's finale as it didn't had to rely on PIS moments in order to carry the episodes story through. the AU verses were interesting, especially the first three with Sombra (love the war setting), Chrysalis (Love seeing Zecora being a leader and fighting a hopeless war against the Changelings), and Nightmare Moon ruling with an Iron fist over the ponies to where all her friends are angry servants to her are interesting enough for fan fic writers to latch onto. Starlight Glimmer was great as a villain and was single handily beating Twilight like a drum throughout the episode. Also with Starlight Glimmer getting the reformation treatment, I'll be curious to see what they have in mind for her.
However, as with any time travel stories, due to not giving enough time and material to all of them, there were many unanswered questions for how those AU presents had happened, especially at the end where they started feeling like rushed filler at the end. Starlight Glimmer's reformation was too fast. Also, the episode seemed to have whitewashed or forgotten some of her villany as it seemed to change her motivation from achieving equality for all ponies to her vision (considering how she had a plan for those captured cutie marks, especially Twilights, likely got foiled however) to where she appeared more nefarious to being a hurt soul who wished to not be hurt again of losing her friends to their cutie mark and destiny.
It's not a bad episode and I certainly enjoyed it to perhaps considering it the second best finale, though that is not certain as I need to reflect more on it, but it's certainly not S1 finales equal in quality.