I’m sorry, but some of your edits miss the point. The Skywalker lightsaber being split into two and being repaired with a band of metal is the equivalent of Luke’s robotic hand, it serves to remind us of Rey’s failure in TLJ.
Snoke being a creation from scratch explains why he never interfered during the events of the original and prequel trilogies, it turns out he never even existed at those points in time.
The whole point of Rey being Palpatine’s granddaughter is to reinforce her subconscious, irrational core belief that she is worthless, she becomes convinced that her lineage is the reason she is falling to the dark side and committing sins like unleashing Force lightning onto the transport and stabbing Kylo Ren in the chest with the very lightsaber he used to kill Han.
After she was abandoned by her parents, she subconsciously developed this irrational core belief that she is worthless, she subconsciously hates herself (she doesn’t actively hate herself, it’s a subconscious thing), she believes this lie that the only way to feel happy, to feel loved is if she gains love and worth from others as well as if she pleases others which would then result in said others giving her the love and worth she desires to make her feel happy; it is for this very reason she frees BB-8 from Teedo, why she bypasses the compressor on the Falcon, and why she tells Luke that she would not fail him in the way Kylo Ren did. She is essentially a parasite, leeching off of others to give her what she wants.
After Rey gives into the dark side and mortally wounds Kylo Ren, as I stated, she becomes convinced that her lineage is the reason she is falling to the dark side, so she exiles herself because if she falls to the dark side she’ll make things worse for others instead of pleasing them, she’ll never get the love and worth she wants. She thinks that being Palpatine’s granddaughter automatically makes her even more worthless… that is, until Luke shows up and gives her a pep talk that just because she is Palpatine’s granddaughter doesn’t mean she is worthless (for example, Leia knew of her lineage and yet still trained her, because she saw the spark or whatever in her).
She heads to the Sith Citadel on Exegol (the Citadel represents the subconscious and hidden part of her mind) to confront Palpatine and end the Sith for good, but he convinces her to kill him so she would become Empress and have control over his forces who are endangering her loved ones, her found family, if she refuses her loved ones, her found family, would be killed off; she accepts, knowing that if she becomes Empress and prevents the Final Order from killing her loved ones, her found family, she would obtain that worth for as long as she lives her life as Empress. Suddenly, Ben Solo, the one person she has had a close connection to through the Force for a long time, comes backs for her, showing her that he truly cared about her, that she is valuable, even if she never becomes Empress; this allows her to refuse the ritual and stand against Palpatine. However, he then drains most of her and Ben’s dyad life energy (symbolic of how low self-esteem drains one of life and happiness) and gets rid of the one person who has showed Rey that she is valuable, leaving her all alone once more in the darkness; that is… until she calls out to the Jedi of the past, then all of them respond and convince her that she isn’t alone, that she is capable of rising, etc. This convinces her to refuse the lie she believed her entire life, that she is worthless, that she can only feel worth something if others give her their love, so she finally faces against Palpatine. He spits at her about how she is nothing and how she is unable to stand against him; she ignores his remarks and responds back with her own, self-made sense of self-worth and self-esteem… that “she… is all the Jedi.” She permanently destroys Palpatine, the personification of this irrational core belief, once and for all.