This is my analysis about yuuri personality (sorry if it's a bit lacking):
In the school, she acts like a refined girl , but in reality she is a prideful girl with a positive personality and easily get carried away. Being gifted with beauty and talent, and how she is quite famous in school, this make her overconfident and always acts rather arrogant, seeing herself as an existence that above others (even comparing herself to Zeus). Due to this, she always tries to take lead over others. She is shown to be quite lazy, to the point she makes Kanako to do cooking and cleaning for her (which Kanako complies happily). Despite so, she also hide her insecurities through this attitude. She dislike boring things and prefer to live her life full of excitement. the main part of her personality, being positive, arrogant and overconfident remains the same for the rest of story, although after going out and fall in love with the protagonist, she developed a dere side has become more attached to him (even more as the story progresses) and try to be more independent for him.
as far as i know, yes , as far as i know (i said this 2x because it's important), arrogant type heroine tend to cast away this part of them when they fall in love with protagonist, but yuuri is not. well, i recommend to try to play at least 1 hour and you will find her personality and interaction with protagonist to be quite fun. unless you are not fan of charage and light-hearted story, this one is not for you.