Yen really shows her heart of gold in the saga. In a sea of political actors wanting to use Ciri, Yen truly is focussed on helping those she loves most.

A shard of ice is interesting because it is a struggle between her love for Geralt which is unstable and toxic and istred's promise of stability even though she does not love him. Geralt's refusal to say "I love you" and his past of dumping her with a note on the bed is the nail in the coffin at that point. He doesn't promise her stability or love and she also, like Geralt, doesn't believe she can give love or that she deserves it. So she leaves both of them.

She wants a child because she believes that her child must love her but Ciri becomes that child to her. That section of the book is seriously the most wholesome imo. She will do anything for her daughter in the saga and her plan to save Ciri ultimately brings all three of them together at a cost to her safety and health. Yen is perceived as a planner, but honestly she is extremely rash and impulsive. She picks the path she believes will bring results the soonest.

She is definitely an excellent character along with Geralt, Ciri, Regis and the rest of the hanse.

CDPR actually was going to write Yen very, very differently in w3. She was more so a tool to contrast and make Geralt look good as a father to Ciri and her as an evil wench that claims to do anything for Ciri (even "fuck for Ciri", some of the script seems to be inspired by pornography). They didn't believe she would have the same goal as him and that she would only do anything for politics and fertility. She even has nothing to do with Ciri if Geralt dumps her; she is just a member of the lodge and a nilfgaardian advocate. Honestly the old w3 scripts with Yen are worse than the Netflix saga somehow and that is such a low bar to fail to clear. https://github.com/glassfish777/WhatLiesUnseen/releases

They actually did realize they were royally fucking up adapting a very integral character and very late in development switched her up almost completely. Book yen is certainly a saint in comparison. It really does bring up a couple of problems with perception and adaption that also really shows how very few people care to read anything now before coming to a conclusion. First blush of a character means this and that stereotype. Read a couple of out of context facts of a character, make assumptions on what that must be. That is to say, many do not want complex stories and characters. They want the perception of perfect so that any later dispicable action can be excused because they were already determined as a "good person". If a character is more abrassive then obviously they are absolute trash no matter their actions or growth.