Hi, it's me again. I'm the one from the other thread. I'll just put some insight on my views on qwertyuiop's comments, which I mostly agree on, and complement my own from the other post.
Honestly, I'm not familiar with the American metric system, but when it comes to personality I do get her. I do see why, in her more casual relationships, she comes off as difficult, seeing that she loves to fight. Making her laugh easily is good advice, I do that myself a lot when I'm around people I'm not close to (co-workers, people I've just met, etc.) and don't want to appear as rude or moody. Maybe giving her few friends where she works, to whom she actually talks to more freely, they don't need to be really close, but it could help you with showing that she's not as angsty and rude as she appears to most people and that she can actually relate to other human beings that aren't family. (I saw a Ruby Jorges there)
As to the part where "She doesn't like people who are extremely dependent but will defend the helpless", I think this could work, but you have to clearly define her principles, for example, linning it up a bit with the part that says that she hates rich kids, you could go by stating that she hates people that's dependant on the money, or their parents' political connections, or their family's prestigious name, but that never actually solve problems for themselves, against defending the kids that have to put up with bullying, or deal with some kind of abuse, or are marginalized and discriminated against.
And this goes for everything she believes. With opinionated people, you have to thoroughly define what they stand for and what they're up against and whether if it's backed up by research or proof, or if it's just misinformed and cultural prejudice. Also, I think is important to note that making her opinionated doesn't necessarily mean that she has an opinion about everything, there are matters of greater importance for some people and matters they've never stopped to think about.
Do define how her competitiveness works, like, in which aspects is she competitive, in which she low-key minds and in which she couldn't care less. You said she doesn't mind about trivial games, but what is trivial to her?
With the social parts, I already talked about some part of it in the other post. As to religion, I do feel that it would be quite important for her since she has strong beliefs, even if she is an atheist or an agnostic.
And about the history part, yes to everything qwertyuiop said. Backstory. Important.
Clashing traits. In some characters, it is interesting to see it at play, but it has to be very well written; under what circumstances is she certain way or believes certain things, and under what others does she behave differently. You need to be careful not to fall into a contradiction or inconsistencies. I don't think you have that problem though, it's just a matter of polishing her principles.
Still, love her, very ISTP relatable. Good job :)