Adults Are Useless: In the Infinity Library arc, Hayate and Nove accompany the group of Inter-Middle participants. Fabia Crozelg fights the participants and is able to take down most of them, but neither Hayate, nor Nove nor Yuuno are there to help them. And among the late teen participates, Micaiah is one of them who gets curb-stomped, only Victoria remains, who on the other hand fights with Corona against an army of devils and cannot fight Fabia directly. Hayate just arrives when everything is over and she only repairs the collateral damage.
Always Someone Better: The four main characters are just 10 to 12 years old rookies and they participate in the Inter-Middle Championship for the first time. Of course, there are plenty of characters who are much stronger than them.
Art Evolution: The art style changed after a few chapters. Noticebly, Erio looks older and has a different hairstyle in his appearance in chapter 11 than in chapter 2.
Canon Discontinuity: The first chapter features Vivio sending other characters a picture of herself and her friends, Corona and Rio. It's ambiguous whether it happens at this moment or in the past; Lutecia looks noticebly younger than in her actual appearance, but the biggest contradiction is Hayate. She and Reinforce Zwei wear their Ground Forces uniform and Hayate has the same hairstyle from StrikerS, despite she had already longer hair a year after that season (even if it's not the same hairstyle like in ViVid or in Force) and she already moved back the Dimensional Navy right after the disbandment of Riot Force 6, but Vivio became friends with Rio in the end of their third year, which makes this event implausible.
Did you notice there are two Fates, but no Zafira? And that Vivio is in the opposite team of her friends?
Curb-Stomp Battle: A few on- and off-screen ones during the opening of the Tournament Arc. Chapter 25 has a montage of Team Nakajima curbstomping unnamed opponents.
David Versus Goliath: Happens frequently with the newcomers and the veterans in the Tournament Arc. It's only played straight once, and the winning newcomer isn't even a main characternote Or she is. Miura has the reputation of a main character.
Demoted to Extra: With the exceptions of Vivio, Lutecia and a few of the Numbers, all the other recurring characters have had their screen time cut, even Nanoha and Fate. This isn't a bad thing though, as Vivio and Einhart do a very good job of copying their dynamic and a new generation of magical girls are stepping in to fill the gaps. Also, most of the characters from previous seasons are overpowered in comparison to the Inter-Middle participants.
There is also a balance. Most characters who are Demoted to Extra in ViVid appear more often in Force. Likewise, almost every major character in ViVid doesn't appear in Force or is barely seen, like Nove.
Fantastic Fighting Style: Strike Arts, Kaiser Arts or Black Jeremiah. All the named rivals in the tournament arc have some uniquely named fighting style, but it's not clear whether they are officially recognised or just their own variations. Parodied with Harry's ore-shiki, which means "Me-style" or "Style of Me".
Full-Contact Magic: All those heavy-impact punches and kicks still count as magic. Vivio especially, she's attempting to weave magic and martial arts together, something that her ancestor was apparently a grandmaster of.
Genre Shift: On the surface it appears to be an attempt to return the series to its roots of Magical Girl cuteness, but it's so overloaded with various martial-arts related tropes, one could almost be forgiven for mistaking it for a shonen fighting series.
Hero of Another Story: While the tournament follows the underdog story in Vivio and her friends, the story also fleshes out the friendly rivalries and camaraderie of the returning contestants like Sieglinde, Victoria, and Harry, making it difficult to chose whether to root for the newcomers to overcome the veterans or for the veterans to survive long enough to finally to conclude their personal duels.
Hit Points: Used in both the mock battle and the Inter-Middle Championship in order to prevent the fights from dragging for too long and increasing the risk of injuries. Even so fighters can be KO'd before their hit points reach zero.
Idiot Hair: Many characters introduced in ViVid have ahoge for no reasons. It's easier to count the characters who don't have ahoge.
Improbably Female Cast: While the previous seasons was already bad with this trope, ViVid takes it Up to Eleven than any other series of the main continuity. Only two new male characters, one of them being a Posthumous Character, have been introduced in ViVid. There aren't any featured male Inter-Middle participants despite it's not restricted only for females, as Erio has the option to enter it in his world. So far, the only male characters who have appeared in ViVid are Erio, Genya, Claus, Voltz, Zafira, Edgar and Yuuno. And they don't have much screentime either, two of them are just only cameos.
Let's Get Dangerous: What everyone looked like to Einhart when she first gets to see Nanoha & Co. in action.
Einhart: It must be wonderful to have two such gentle and family-devoted mothers... but they can do magical combat too?
Nove: *starts collapsing in giggles behind Einhart and Vivio*
Power Limiter: The girls form Team Nakajima all train with bracelets that act like training weights, draining their physical and magical energies to help foster their growth. By the end of their training they are wearing four of them each. Their introduction even included a quick Continuity Nod to Nanoha's Training from Hell in the A's manga, where Nanoha used a cruder version with Raising Heart's Pressure Mode.
Reality Ensues: While Vivio and her friends are the main characters, it is noted that they are still amateurs going up against very seasoned professionals. With the exception of Miura, who was trained personally by the Wolkenritter, every time one of the girls went up against a veteran (Rio for Harry and Einhart for Sieglinde) ended up in a loss. Even against each other, Vivio was a hobbyist compared to Miura's dedicated practices.
Super Robot: In much the same way as the previous casts tended to be seen as expies of either Real Robots or their pilots. Those individuals that are reincarnations/decendants of ancient warrior-kings tend to come across as general expies of these.
To Be a Master: To be declared the strongest in all dimensions (at least, within the 10-19 age group).
Tournament Arc: The DSAA Inter-Middle Championship. The whole tournament itself is structured in several other tournaments. First, after going through the preliminaries, the fighters are going to fight in the City Tournaments. Then, the winners of these tournament will participate in the World Tournaments, and finally the fighters who are end up victorious will decide the champion in the Inter-Dimensional Tournament. Since the story is about Team Nakajima's first tournament, the Tournament Arc is actually only about the preliminary.
World of Badass: If there was any doubt before ViVid made it obvious that kicking ass and taking names is a requirement for any girl over the age of ten. They even have an Inter-Middle Championship where the best of the best go to beat each other up with magical kung-fu for fun. With no shortage of candidates.
However, most of the participants are still much weaker than the TSAB mages.