Inej doesn't have a brother in the book series. Why make that change unless it is a big deal?
- Seems unlikely, Inej's brother grew up with her and their family, while Mal grew up with Alina in the orphanage.
In order to incorporate the Crows in future installments of Alina's story, jurda parem will be invented earlier than it is in the books and Kirigan will try to use it in some way.
- As of the end of Season 2, jurda parem exists, so definitely plausible.
In the books, Dunyasha Lazareva has little overall importance despite serving as Inej's counterpart towards the end of Crooked Kingdom. She has no prior connection to the gang war in Ketterdam and was only introduced as an antigonist who could go toe-to-toe with Inej. There's good odds that Dunyasha might recieve an adaptational expansion in later seasons of the show, and what better way to set up the role of the White Blade as Inej's foil by making the character her brother?
In the books, Nina briefly resurrects Matthias after he's killed because she's a) freaking out and b) on jurda parem. She undoes it really quickly because his eyes are black and she hears some creepy whispers. In the show, we know actual magic like resurrection causes merzost.
Alina obviously has some merzost problems, and it'll turn out that some of it infected Mal when she was rezzing him. He'll slowly become more violent, etc, and eventually Alina will notice and have to kill him with her Sun Summoning to remove the taint.
In the books, jurda is a normal stimulant and parem the derivative. They're near-identical, and jurda is incredibly common, so parem is almost impossible to regulate. It would be a good fake-out at the very least.
In the books, Nina eventually develops the power to somehow commune with the dead and speak with their voices. She'll use this power to talk with someone with pivotal information about the Ravka plot who also happens to be dead. Alternatively, she'll get asked to use it in the "I just want to hear their voice one last time" sort of way, possibly by Genya (for David) or Nikolai (for his guard buddy).
Alternatively alternatively, she'll use it to reveal Kirigan's not dead-dead (in concordance with the "Kirigan will be resurrected" WMG above) or that something is up with Mal (who was dead for a cool five minutes, and may have Come Back Wrong considering Matthias' example of such in the books) or Nikolai (who might be considered "dead" at a certain stage of the shadow monster infection).
A thousand years of separation doesn't go away easily, and there's pretty strident nationalistic sentiment from what we see, with the general dude wanting Alina dead because she might be able to tear down the Fold and thus jeopardize the independence movement and even immigrants to Kerch making a distinction between East and West. With news of Alina using the Cut and Nikolai maybe being a freaky shadow monster, West Ravka will collectively say "well, screw this noise" and revolt.
They already had this partially with the hallucinogenic drugs episode, so there's precedent. It would be an easy way to have the characters with less development and/or backstory elaboration (Jesper, Wylan, Nina, Inej, possibly Tamar and Zoya) get some, while those who had that kind of experience already (Kaz, Tolya) can be conveniently out of range.
It happened twice in Season 2 in the same episode - and in a relatively short timeframe to boot. She's probably not enthusiastic about it happening a third time.
He seems to be lined up to share his book backstory - he's dyslexic, mentions having "a tutor" to Jesper before backpedaling, and is very familiar with companies that rich people would be aware of, as Hoppe & Sons seems to be a piano string repair company. Additionally, the last big blowup in his relationship with Jesper was about Jesper "keeping secrets", which would be pretty hypocritical if Wylan does have his book backstory and hasn't revealed it to anyone yet.
The show also seems to be hinting at the Ice Court heist from the books given the focus on Fjerda, so he'll have to pretend to be an attendant to somebody to get in, and will do so very well. Jesper will ask him how he was so good, the truth comes out, and so on.
She was very unhappy with being told Genya wouldn't be arrested because she wasn't at fault and Nikolai ordering her to a nunnery. She's also pretty racist, of both the normal and fantastic variants. With the unrest in Ravka, she'll declare that Nikolai is illegitimate and partner with some noble house in an attempt to "reclaim" the throne and "restore order to Ravka", playing on the now extra-potent hatred of Grisha as a result of Kirigan's actions and the Fjerdans doing a terrorism using parem and a Grisha.
With Nikolai's new shadow-creature infection Baghra ended up not "truly" dying thanks to the existence of a new nichevo'ya in Nikolai being connected to the one she summoned to kill herself with. She's understandably (more) cranky about these events, and will mostly focus on helping Nikolai deal with his infection and any other issues that might happen, as well as teaching him about how the Little Palace and conscription of Grisha are bad actually.
David was the only person who told her that she was beautiful on the inside, and she's been shown to have a huge complex about looking beautiful - Tailoring yourself at three is not the sign of a great self-image. With him presumably dead and the stress of suddenly having the public aware of her scars, she'll snap and insist on outside perfection for everything and everyone, even though behind the scenes is a disaster.
