She is already the Mary Sue to end all Mary Sues, do we need to give her more?
Well, in the novels she is just someone who everyone wants to fuck because of her super-DNA and possible descendants. By herself, she was pretty much nothing. I did not like this "the war for Ciri's cunt" approach. So I was pretty damn glad that given events in TW3, it may be interpreted that everyone was wrong, that in the prophecies about the future seers saw actually her, and not some her distant descendant, and that her genitals are not important at all. She is.
Yeah, Ciri herself is not perfect. Others thinks the same (Eredin saying she's a golden nugget in a pile of manure), others want to use her.
The goal is for her to not be the chosen one. Others make her think to be a chosen one, unfortunately for her she has Elder Blood. That's not remotely a pros, I mean she's not interested in wandering through dimensions. I can't see Ciri character as a perfect-in-everything-she-does-Mary-Sue cliché, even if it seems so, because she doesn't want this, she's not like "hey I am the chosen one, I can do this and that", and when she tried to use her power she almost failed, I mean she can't have control on that because it's a power too much higher for her and she need always help. (Ihuarraquax, Nimue...).
I'm sure that if she was remotely perfect she would have found Geralt at first try while wandering through dimensions (again, with the help of Ihuarraquax because she couldn't control the power). That if she was, she would have avenged Mistle and the Rats in Jealousy when Bonhart killed the Rats , not to talk about when she defeated him thanks to the tricks learned in Kaer Morhen.
[SUB](I would be extremely disgusted by Vilgefortz later character development instead...tried to do what...well what he wanted to with Ciri delicate parts. Pretty much the war mentioned earlier. This sudden change... I did not like it, he was dead as a nice villain character for me in the exact moment he mentioned something related to the world and power when he talked with Bonhart for the first time. RIP.)[/SUB]
Geralt is very good in what he does, a lot of people know him as the famous White Wolf, the witcher with white hair. Yet even if he is that good, he's not perfect, he has flaws, both in his character (as it must be) and in his profession. He's despised.
Ciri is good in what she does... not suddenly but after a time, she's not an adult. She would later know by...few... as "Lady of the Worlds" (Aen Elle and Nimue perhaps?) she hates Galahad calling her "Lady of the Lake" because she is not what she wants. Yet, even if she can be good, she's not perfect, she has flaws (again, as it must be). He's despised (Avallac'h, Eredin, Bonhart, Vilgefortz).
She's not important as person herself, at least, when not being the heir on Cintra throne. She is only a mere tool.
Geralt himself is not important, he doesn't consider, he ony wants to stay neutral. Unfortunaly for him, that can't be possible. And more than that, it's Ciri story that ends with Geralt's "death". Both are important figures for each other.
I was pretty sure that Avallac'h wanted to use her for real, he did but... for other purposes, being still obsessed with Lara. Eredin mentioned something like "he betrayed us both" and I was expecting some kind of plot twist... that didn't happen for real. But that's another story.