We don't know why he doesn't want to use his talents for good
He tells us. This isn't his personal fight, and no amount of money would get him to fly what he considers a suicide mission. He's a loner who doesn't care about the fight for good and evil, which was established earlier when Luke failed in appealing to his sense of morality ("Let's save the princess!") but succeeded in appealing to his sense of greed ("She's rich"). He's conflicted about it, but he leaves the Rebel base and then we cheer! when he comes back. Han's arc is clear and impactful, Finn's arc is muddled and meh.
As to Rey refusing the call to adventure tell me how that isn't Han's character to a T pretty much until the Empire attack Hoth?
No. Han's arc is going from a selfish loner to a team player, forming a connection with Luke and Leia, finding a cause bigger than his own needs, etc etc.
It would be as if Han were told in the first ten minutes of ANH that he has to become more selfless, and he spent the entire runtime denying that only to admit at the end that, yeah, maybe I do need to change, rather than spending his time forming bonds with Luke and Leia and becoming invested in their cause through them.
Rey's arc is denying the call to adventure (literally, the little green bartender alien tells her that this is her destiny, Rey refuses and doesn't accept until the end) for the duration of the runtime.
And then Leia. Yes she's a princess. Yes she's involved with the Rebels. In what capacity though? What is her ranks? She gives orders to people like she has authority but that authority is never established. Is she a general? Is she a captain? A lieutenant? A major? What? Is she allowed to give people orders simply because she was a princess of a planet that got blown up? And why is she risking her neck crossing the Empire when she's not a trained soldier in the first place. Easy answer is heroism and that's all you really need, but if we're applying the strict scrutiny you're applying to D!SW, then one must ask why she doesn't simply remain with the commanders since she seems to be some high authority of some kind. Why is she out there risking her life carrying sensitive information. Is NO ONE else more disposable capable of something like this
Stop comparing character issues to logical nitpicks.
I just personally don't see what is so damn essential to finding out the full roadmap of Finn's psyche to figure why he defected.
It's the other way around. Why he defected gives us a roadmap of Finn's psyche, explains who he is as a person, tells us what drives and motivates him and
(most pertinent!) should serve as the basis of his character, given it's the first time we see him.
Finn's character in TFA is torn between going home and staying with Rey. This means nothing to us, since we haven't seen what "home" is for Finn, which means we don't know what it means
to him, and if we don't know what it means to him, why would it mean anything at all to us? What they did show us was him breaking in combat and defecting- so why is his character written about wanting to go home instead of that?
The solution is to either rewrite his character from the basis that he is a until-recently-slave-soldier who has never lived life on his own, never had a real relationship, never had a real name....or start the film with a scene that features child Finn at home. Show us what he has lost, and what he stands to gain by going back, so there's some actual drama involved in choosing between Rey and going home.
What you
DO NOT do is open with a scene of Finn psychologically breaking at the first sign of combat, then proceed to never bring up that angle from a character perspective again. Or establish that Rey is committed enough to endure a decade and change of literal slavery, privation and destitution to wait for her parents to come back (despite the obviousness that they won't) to the point that she will refuse all opportunities to move the eff on, and not explain or dramatize the source of this determination.
Rose's first scene in TLJ establishes two obvious things about her: her sister has just died, and she is a true believer in the Resistance. It does this so well that Rose flips from gushing fan girl to shooting Finn first in a blink of an eye. So when there's a scene later where Rose has an opportunity to run away with Finn, to abandon the Resistance certainly doomed to die, her refusal
is coming from somewhere. (Not that Rose is a particularly good character, I'm trying to keep the examples to Star Wars). When she gives up her sister's medallion to del Toro, it's a heroic sacrifice because it's all that she has left to remember her sister: when del Toro returns the pendant, we think that it's character growth from del Toro (psyche!).
Luke is written as an every-man but other than being a relatable audience vehicle, his character motivations are not fleshed out in any way
Luke wants to leave home and make something of himself, as well as the struggle between wanting to become who you are and your commitments to home and hearth. This is something literally every person in America will empathize with and understand. Hence why Luke Skywalker is a cultural icon: he captures what it means to be an inchoate young adult in the 1960's- and really today.
How many people do you think will empathize easily with a person who willingly spent a decade as a slave, waiting for parents never to return? Or a recently liberated child soldier?
Hence why Luke works with minimal explanation while you should have some for Rey and Finn.
The problem with Rey is that Abrams and the braintrust wrote an anti-Luke. Luke wanted to get off his godforsaken rock and make something of himself, but is basically forced to stay; Rey wants to stay despite ample opportunities to leave. Which can work
if you then ask yourself "Why would someone do such a thing?" and then write her character based on
that.
The problem with Finn is that Abrams and the braintrust wrote a character as "DEFECTOR STORMTROOPER", but rather than thinking what might make such a person, they filmed a competent scene in which, via shorthand, it's communicated that he's defecting. Bank on the audience presuming that of course he's defecting! He realized the Empire are the bad guys! and you get Finn: a character with little actual character.
To emphasize this point: explain to me, as simply as possible, Finn. What makes him tick?
Why is Finn who he is? 'Cause I see a guy that is an amalgamation of traits without any driving focus to unite them. The most egregious example is staging Finn's opening as a guy who refuses to kill innocents, helps his fellow soldier- yet fails to make much of a statement on his character. It's using a powerful scene as setup for plot devices rather than character.
with the in depth look into a stormtrooper's defection
But in terms of the characters complexity, Star Wars has never had robust and complex characters
I'm not asking for an in depth look or a character study. Finn defected because X. This makes him Y person in this story.
If X doesn't cause Y,
show us the scene that does.
