Well sure, the game doesn't really mean much without her. The issue for me is that I'm not someone who read the books, so I had no context or attachment to the character really. From my recollection she was really only mentioned in passing in the previous games as well.It is definitely more concise as it is a much shorter game... meant to be played several times over many paths in order to get the full context of what was going on. Add to that it lacking a post game.
Funny though, I ended up caring a fair bit for ciri's side of the story. Playing the witcher 3 it really feels like it is all about her and without her it just doesn't work. I was kinda annoyed at the requirements to get good endings with ciri. Because IIRC there weren't clues or context regarding how to get the good ending, you just pick options barely being able to tell one is definitely bad and the other two seem equally good. As is the game is actively screwing you into getting a bad ending....
I sort of got more enjoyment from Letho and yes, even the amnesia trope, since most of the second game was grounded in grit or political intrigue rather than something like Magical Elves from another dimension trying to capture a quasi-Mary Sue I had no real attachment to. I understand that would be much different for people who were familiar with the novels though. Ciri worked fine as a plot device for the first half of the game and the exploration aspect, but I guess I didn't feel much of a payoff in the end. I just think she's ... sorta uninteresting.
It sounds like I'm being overly harsh there, but it's not really my intention. The story didn't really detract from my enjoyment of the game funnily enough, and I still have yet to play the DLCs which seem to be rich experiences detached from the main story so maybe my opinion will change.

