So I finally saw the My Little Pony movie.  I actually enjoyed it.  Most likely a 4.5/5.  Not perfect, but still awesome.

But you ask: What if you were in charge of the sequel?  What would you want in it?

The ideal plot is similar to the first.  Except this time, the new foe is a concerned Alicorn Empress named Eternia.  Her goal is to conquer all lands so that her lands would be protected.  When Celestia, Luna, CAdence, and the Mane 6 went on the counter attack with the Royal Guards(As well as the former servants of the Storm King), they were completely curb-stomped, and CAnterlot is laid in ruins.  As a result, The Mane 6 and Princess Cadence are taken captive by the Empress(Save for one: Pinkie Pie) while Celestia, Luna, Starlight Glimmer, DIscord, Pinkie Pie, Capper, Tempest Shadow, Captain Celaneo and Princess Skystar made their escape to Mt Ares.

As Queen Novo gives shelter to the misplaced Ponies, Starlight was hit by a Plague Orb.  Novo placed Starlight in a healing ward to prevent the plague from getting to her, as Celestia and Luna lament the loss of Equestria to this new foe.  Starlight gets a nightmare about losing Twilight Sparkle, and even Tempest Shadow became concerned, with Pinkie Pie playing the morale chief.  Things take a turn for the worse when Mt Ares and Seaquestria are invaded, forcing everyone to evacuate.  Even Discord is no match for the Empress as her power is even greater than any creature.

It didn't take long for reinforcements to arrive in the form of Dragons, Yaks and Changelings.  They form an alliance with the Republic of Equestria(Lead by Celestia and Luna) and the Hippogryphs(Lead by Queen Novo and Princess Skystar).  The leaders of all the groups have named Princess Celestia the leader of the Equestrian Alliance Army, declaring her "Celestia Prime."  War would now begin against the Timeless Empire from the far west.  During the war...

-We see love bloom between Captain Celaneo and Capper

-As Starlight's condition worsens, she thinks long and hard about Twilight Sparkle and Sunburst.  She chose to fight alongside her fellow ponies than to die alone with all available cures destroyed.

-Rainbow Dash, Applejack, Fluttershy and Rarity have escaped the clutches of the Empress, with a small resistance group.  They join in on the war

-Twilight Sparkle, still in captivity along with Cadence and Flurry Heart, learns that Empress Eternia is the mother of Celestia and Luna.  Which means they were originally from the Timeless Empire, and she's over 2000 years old.

-Even more so, it seems the Empress had her reasons to invade Equestria, besides recover her children.  She fears that the world would tear itself apart, and that it would creep into the Timeless Empire.  The irony is that they have united, and war is now within the Empire.

-Tempest Shadow is honored to fight alongside Equestria, after all she's been through serving the Storm King

-It is said that the Plague Bombs are like the Obsidian Orbs, except that it infected the user with a plague.  Even more so, the plague cannot be transferred through Air or Water.  It only affects those who were caught in the cloud.

At the Climax of the film, both sides are at a stalemate, even the EMpress is starting to weaken from endless combat.  Everyone is tired to continue fighting.  As the war began to die down, a weakened Starlight approached Eternia, asking her why is she doing this?  When the Empress responded, Starlight points out what she's been through, and that she nearly let her own selfishness destroy Equestria.  The Empress is even shocked that  a plague bomb would hit Starlight, and that it came from one of her own.   Starlight then dies in the Empress's arms, succumbing to the Plague that was eating her.  As the Empress realized what she had done, she was hit with an even more powerful Plague Bomb.  Betrayed by her own Advisor.  She apologizes to her children before also dying.  

Celestia and Luna confronts the Advisor, who uses Twilight as a hostage to force everyone to give up their magic.  Reluctant, Celestia and everyone else agreed, making the advisor more powerful than anything in Equestria.  The Advisor uses the magic to bring terror and fear across the entire planet.  Even the Windigos were no match for this monster.  The Advisor's dream: Leave the planet in ruins, and become a god/goddess.

Luckily for Celestia, she had a backup plan in case that happened.  The Elements of Harmony. She gives them to Twilight and her friends, and they use them to defeat the Advisor, reducing the monster to a former shell.  

But what about the recently deceased Starlight Glimmer and Empress Eternia?  Twilight was told of a cure: A Bath underneath the palace with the same waters as Seaquestria.  Celestia places her mother and Starlight in the waters.  At first, it didn't seem to work, but the waters took effect and brought Starlight and Eternia back to life.   Celestia and Luna embraced their own mother, while Twilight and Tempest gave a big hug to Starlight.

In the end, grateful for being given a second chance, Eternia has formed a treaty between the Timeless Empire and Equestria, creating a new alliance.  Celestia was to retire from the name of Prime, but the other rulers insisted on keeping it, to serve as the Prime leader of the Equestrian Alliance.  And to top it all off

Two weddings: Starlight Glimmer and Sunburst, and Capper and Celaneo.

The title would be: My Little Pony: War of the Timeless Empire.

And the voice for Empress Eternia?  Gal Gadot.