Leslie had the support of her new family and the children of the past to help her through the darkest of times.
Tina has no family to help her with her dark magic until it became too much for her to handle until Reinier showed up and protected her and keep her positive to prevent her sigil from growing and magic going rampant.
Tina's not weak, she only had lack of support from family that made her feel powerless until she was saved by Reinier.
Exactly, plus didn't Leslie have a second chance and went back in time unless I remembered it wrong.
True, but the thing is unlike Tina Leslie had this self-realization and inner rage all along that allows her to turn against her Abusive Blood Family. There is no Shiny or Dark Prince who happens to pity her and finds her pretty enough to save her.
She gained the support of a new better Family after she started her Scheme and Revenge. Furthermore her spirit predecessors gave her a fighting chance, however Leslie did the active work herself to change, survive and heal.
We don't see that often a FL with that much agency, assertiveness and strength.
Tina's Personality and Growth on the other hand xully depends on how much a handsome powerful ML loves + pampers her. It's a more convenient conservative Romance Narrative about a Cinderella Damsel Type.
Leslie never regressed.
She just realized on her own how shitty and worthless her atrocious Family is.
While that may be true, there are two different type of people who face abuse like this. People like Leslie who didn't outright give up on getting away from her abusive family, and then you got people like Tina who lost her hope until she snapped and her magic went on a rampant. Sometimes you need support like in this story.
But does 'Support' only means being the FL who can only be saved by a Elite Prince/King or Duke?
Not necessarily if we apply it to real life scenarios, but it helps to have some like Reiner to be her support who has the means to take care of her.
However, some people just want the bare minimum and will be grateful to be helped and have hope again. There are stories I've read where it wasn't any of those MLs, one was a Count who turned into a Duke at the end of the story, granted it wasn't an abusive storyline but an example.
There's also nothing wrong with someone of high power rescuing the FL who needed the help, they won't care who saves them, as long as they can be freed from their suffering.
How many times have we seen the scene where the Evil Sister mocks and humiliates the Heroine in a jail prison room???
This FL is with the power of darkness is so much weaker than the MC Leslie Shuya Salvatore (The Monster Duchess & The Contract Princess) who emancipated and liberated herself.