Pretty much what Mephasm is made of. He never lies, he never fails to be anything less than absolutely polite, and he tries to give the party every advantage and help that he can, regardless of his circumstances. It's generally accepted that he's a Manipulative Bastard, and the most evil figure in the game, despite him never doing a single thing to justify it — in fact, it just makes him all the more magnificent. Cue fan complaints when he never shows up in the sequels.
Shandra's whole motivation for always following you around in Act II — the game doesn't let you leave her behind! — is because bad things tend to happen to her if she doesn't stick very closely to the PC. That disaster in Ammon Jerro's Haven? It happens when she is forcibly separated from the PC by a teleport.
The player is allowed to choose a background, which mostly affects the early game or interacting with those from West Harbor. Yet you can also see all but one archetype in the characters around West Harbor, who also reflect their traits.
Bevil is the Militia background - while there are a number of characters in the Militia, he is the one who exemplifies it most: good at arms and keeping them up (parry, craft weapon/armor), but can easily be influenced by someone he looks up to like the player (a rather notable Will penalty)
Amie is the Wizard's Apprentice, of course: well learned and highly skilled with spells (bonuses to spell-related feats), but can miss things and is not really well suited to take a hit (penalties to Fortitude, not that it would have helped her against a fireball)
Wyl Mossfeld is of course the Bully background, throwing his weight around. He's tough, one of the biggest brutes in the West Habor Militia (bonus to fortitude) and intimidating, but has a hard time making nice such as when you find him bleeding later (penalties to diplomacy).
Orlen represents the Farmer background, being exactly that. He may not be able to figure out exactly why Lewy's hog was so large (penalty to lore), but he was still able to figure out that something was wrong from other tells (bonuses to survival and spot).
Though he leads the militia, Georg is the outright Tale-Teller: he spins yarns and can actually sound convincing (or know things that others do not), yet he is prone to being distracted when he tells them (penalties to concentration).
Brother Merring is of course the Devout: it is his sense of faith that drives him and gives him strength when by all rights he probably should have walked away (bonus to Will), but also can have a hard time maneuvering in to make the inroads he needs (penalty to diplomacy) despite being one of the nicest men in the village.
Flirt/Ladies' Man seems hard to place at first as there is not much obvious flirting going on, but Retta Starling may have been a former Flirt as she is shown to be mediating and attentive (diplomacy/listen bonuses), but is, well... not particularly scary (penalties to Intimidate).
The Troublemaker is, of course, Kipp: stealing from Tarmas and getting into all sorts of mischief when he really should know better (penalties to Will), but also very good at dodging trouble (bonuses to Reflex and Rogue skills).
The Wild Child is Daeghun: as he says himself, he was raised in the wilds and that the ways of civilization are foreign to him (penalties to Appraise and Diplomacy, both tasks he leaves to the player), but he is also a masterful tracker who has the habit of showing up when he needs to (survival, spot, hide/move silently).
The only one missing is a Natural Leader - the closest the village really has is Georg, but he is more of a Tale Teller... of course, who else would be a natural leader besides The Hero - that is, the player. And even if they do not take the background, they end up drawing many to them and are looked up to when the village needs help, even if it means throwing themselves into danger.
The Natural Leader could arguably be Cormmick, whom the PC is explicitly compared to quite often since he was also very strong, talented and charismatic Normal Fish in a Tiny Pond who eventually became a Lieutenant for the Neverwinter Guard. While the PC is forced to leave West Harbor due to external circumstances, most villagers agree that it was only a matter of time before you moved on to bigger things too.
Neeshka is True Neutral because she's caught between two conflicting moral influences - being part devil gives her innate Lawful Evil tendencies, but her worship of Tymora shows a desire to be Chaotic Good - and her final fate depends on which side wins out. With low influence, she gives up on fighting her infernal heritage and joins Garius for either lawful (his dark magic gives him command over her) or evil (she'd rather just let the world burn) reasons. With high influence, the player character's support has strengthened her chaotic and good convictions enough that she defies Garius's control and fights for those she cares about despite the risks.
Why does Neeshka display Angst? What Angst? about her incredibly depressing backstory? Because she isn't fully aware of how depressing it is. She knows her parents probably abandoned her as a baby, that she was raised by strict monks in the Temple of Tyr, that she's faced Fantastic Racism for being a tiefling her whole life, and that she has no friends. But it's because she's never had a real family or friends that she starts out non-fussed. She's never had a real basis of comparison.
It's also why she doesn't become depressed till the end of the game: By the Definitely Final Dungeon she's been traveling with the KC for so long that she's gotten a taste of what being part of a family (or at least group of trusted companions) could be. If the player is nice to her, then they're her Only Friend. If they're an ass to her, then it just drives home how alone and unwanted she's always been.
The base game is a Cliché Storm in a World of Snark, which seems different from Obsidian Entertainment 's usual dark and complex stories. However, Obsidian famously loves using a Central Theme. For the NWN2 base game, the theme is to examine the idea of heroes. Making the story a Standard Hero's Journey makes it easier, since the whole story is made of these tropes.
Why were Lawful Good Paladin Casavir and Chaotic Evil Ranger Bishop planned to be in a Love Triangle with the female KC? Why would two wildly different men be into the same woman? Because the Love Triangle would have revealed they're not so different:
Under Casavir's front of chivalry and protection, he struggles with lust and jealousy, which his Dummied Out backstory would have explored. (He was secretly involved with Ophala, then fled Neverwinter to Old Owl Well in disgrace.) Now he's falling for the female KC and often "defends" her from Bishop's "intentions," but Bishop points out Casavir's "intentions" are no more noble than his own.
Under Bishop's harsh Social Darwinist exterior and protests that "our leader can look after herself," he starts to stand up for her as he falls for her. (Such as when he offers to fight Lorne for her, or defends her to a succubus who badmouths her, and presumably would have sided with her in the endgame).
Basically, much like how under Casavir's show of chivalry and phonor he can be a bit of a selfish dick on occasion, under Bishop's snarls that he's only out for himself he can learn to care about and defend others. Unfortunately, since the Love Triangle was Dummied Out for time, these themes aren't explored as much.
Speaking of the Love Triangle, Casavir and Bishop embody different aspects of the female KC's Hero's Journey. They can also mirror her potential alignments.
Bishop is from a poor swamp village like her, an emotionally damaged ranger like her foster father, is dragged into the adventure by attacking githyanki (like she was), and if the KC is Chaotic and/or Evil then Bishop's alignment mirrors hers.
In Act 2, the PC becomes Knight Captain of Crossroad Keep under Lord Nasher, in service of Neverwinter, and protects the world from evil by default since they're trying to stop the King of Shadows (unless you choose the "Evil" Endings). Casavir is a Lawful Good Paladin of Tyr who Jumped at the Call to defend Neverwinter from evil, and his Lawful Good alignment can mirror the KC's if Lawful and/or Good.
Whether the female KC chose Bishop or Casavir would have symbolically embraced different parts of her nature and/or adventure. Too bad it didn't pan out.
In-universe, this is why Kaelyn is so set on destroying the Wall. According to her there are entire worlds where the gods have no presence and no-one has heard of them, but the same rules for the afterlife apply...
Where is this mentioned? I asked a similar question on the Planescape: TormentHeadscratcher Page and I heard the wall only applies for nay-theists in Abeir Toril.
It's part of her influence dialog, it comes entirely from the character.
To be fair, Kaelyn's not exactly an unbiased source of information. Plus, the afterlives in other places like Tabletop Game/Eberron aren't the same as in the Forgotten Realms, so she's clearly wrong in claiming that the Realms afterlife rules affect everyone in all the worlds.
The story Gann's mother tells about his father while she ate him. He was still alive and conscious when she was being forced to do it, but he died smiling at her and Gann.
Gulk'aush:They remained ignorant of my terrible crime until I birthed the product of our love. Then they found my beloved and made me devour him alive in front of his son. Even as they forced chunks of flesh down my throat, he smiled at me, at our child.
Add up everyone you kill in Neverwinter and subtract it from the population set in the Forgotten Realms books. You just killed a sizable chunk of it.
The population demographics in the source books make absolutely no sense whatsoever, especially in terms of military forces. For comparison, Neverwinter (23000+ population) has a militia of about 400, about a third of which are off duty. Port Llast (700 population) has a militia of 130 people. Luskan (16000+ population) has a militia of about 300......and 1330 archers that don't get included in that total because no one seemed to bother doing the math of just how many naval troops are present, and this isn't even counting the actual naval crews. The population numbers jump all over the place, as well. Waterdeep's population increases by five times over during the trade season. This would mean that literally almost the entire population of the surrounding area goes to Waterdeep simultaneously.
True Neutral because she's caught between two conflicting moral influences - being part devil gives her innate Lawful Evil tendencies, but her worship of Tymora shows a desire to be Chaotic Good - and her final fate depends on which side wins out. With low influence, she gives up on fighting her infernal heritage and joins Garius for either lawful (his dark magic gives him command over her) or evil (she'd rather just let the world burn) reasons. With high influence, the player character's support has strengthened her chaotic and good convictions enough that she defies Garius's control and fights for those she cares about despite the risks.