Here Minako is much more serious than in other continuities, but there's an instance of her pranking ways that is before everyone's eyes but clear only through Fridge Logic: her song C'Est La Vie. Japanese people pronounce the title Sera Vi, the same as their pronunciation of Sailor V... But, she can actually speak western languages the proper way. Every time she sang C'Est La Vie, Minako was crying to the world "Hey, I'm Sailor V, and you'll never find out in spite of me spelling it out".
Sayonara-Sweet Days plays when the girls read Minako's farewell letter after her death. It's one of Minako's own songs, and the lyrics are tailor-made for this situation-she recorded it just for this occasion.
Minako writes and composes her own songs: C'Est La Vie is her classic sense of humour declaring to the world she's Sailor V while nobody realizes what she's saying mixed to a willing misunderstanding of the meaning of the French saying, while Sayonara-Sweet Dayswas made specifically to say goodbye to the other Sailor Senshi.
Sailor Mars gets an Adaptation Dye-Job so that her Sailor form just has black Rapunzel Hair as opposed to purple. As she's the one soldier who's most recognisable, of course Minako recognised her instantly when they bumped into each other at the church.
When the girls are reading Minako's final letter, the camera shows each of them sobbing-Except for Ami, who is crying but not nearly as hard as the rest. At first you think maybe the actress just couldn't pull it off, but then you realize that Ami wouldn't be crying as hard since she wasn't as close to Minako as the other three were; she was the only one who didn't get any special bonding moments with her throughout the whole series.
In Act Zero's ending, it seemed Luna arrived to seek Usagi shortly after Artemis turned Minako into Sailor V during Christmas time. Since the series proper begins around October, Minako had almost a year as Sailor V to learn backstory and gain experience like in the source material and facing off with Tuxedo Mask several times. Since Minako is very devoted to her senshi job, this explains her cynicism when she first met Usagi and Rei in the series.
In the Special Act, Usagi and Mamoru's wedding is being set up suddenly and in a strange hurry (to the point Ami is abroad due the suddenness), and Usagi has some serious mood swings. They just found out Mamoru got Usagi pregnant.
Sailor Luna in her first appearance doesn't seem to have dangerous attacks. She has her fan and Teleportation Spam; the former just annoys Kunzite. But, as she later explains, her goal wasn't to beat Dark Mercury or Kunzite; it was to try and restore Ami. If Kunzite hadn't appeared, they may have succeeded by keeping Dark Mercury from killing Sailor Moon.
Likewise, Usagi goes Deer in the Headlights when her attempt to revive Ami fails, and Dark Mercury destroys her wand. But the Silver Crystal takes part of her strength in other continuities; it's possible that it was a Hail Mary and Heroic Sacrifice on Usagi's part since she refused to hurt Ami and hoped it would bring Ami back to her senses, at the cost of Sailor Moon's strength. Fortunately, she gambled correctly in the end.
Dark Mercury destroying Sailor Moon's wand knocks out the latter. In other continuities, the silver crystal would attach to the wand and rely on Usagi's strength to heal people. Much as she powers the wand, it also weakens her when Dark Mercury smashes it.
Usagi in most continuities came to resent being a Sailor Senshi and said she wanted a normal life. She gets her wish in this one, which makes the ending Lighter and Softer.
It's a good thing this is an Alternate Timeline; in the main canon, the Senshi losing their powers or needing an upgrade would always happen right before a new foe appeared and curb-stomped them. If the Witches Five or Sailor Galaxia appear, the Earth is screwed.
Why doesn't Crystal Tokyo happen in this timeline? Because Princess Sailor Moon would not be so selfless as to revive everyone and give them immortality. Even if Sailor Galaxia killed Mamoru as she did in the manga, it's more likely Princess Sailor Moon would have destroyed everything rather than purify the Cauldron of stars.
If not for Kunzite toying with Ami and Usagi after the former was brought back to normal, the Dark Kingdom would have won when Dark Mercury knocked out Sailor Moon. It's a good thing Kunzite doesn't listen to Beryl...
Ami's arc for the middle of the series is more horrifying than it appears in retrospect. Kunzite waits for her to be isolated before corrupting her, using Ami's insecurities and fears against her. It's confirmed, however, that he created a separate personality in Dark Mercury because when Usagi finally breaks the brainwashing, Ami is utterly confused that an unconscious Usagi is in front of her, while she's holding a sword and wearing a strange Senshi uniform. In the next episode, Ami is questioning if she can be forgiven when some part of her wanted Usagi dead. That's a lot for a fourteen-year-old to deal with as a soldier.
The roles then get reversed when Princess Sailor Moon appears. Usagi is terrified of potentially ending the world again but knowing that her sadness and pain awakens the princess doesn't help in stopping the disaster. Ami in the meantime is ultimately forced to fight her best friend's Super-Powered Evil Side and seeing what Usagi must have been going through when facing Dark Mercury.
After everyone (especially Rei) insists that Minako should undergo surgery for her terminal illness, she dies — probably from the surgery. To be fair, terminal illness implies certain death anyways, the surgery at least had a CHANCE of saving her.
Minako being alive in the reset timeline where she had never been a Sailor Soldier hints that her terminal illness was the result of her literally working herself to death as a Sailor Senshi. That, or she postponed the surgery until her body couldn't take it.