It would be misleading to call Ciri a witcher, though.
She has no mutations, she doesn't fight with signs and she doesn't use two swords. She may be a battlemage but that doesn't make her a Witcher.
One for sure: since new comic it seems witcheress ending is canon
As i already said.
We should just wait!
I makes no sense to discuss about that now, because right now all we know is that CDPR won't release any Witcher game in the next 5-10 years probably.
So save this Discuss for when the time has come!
A lot can or will change in that timeline. We have no idea how CDPR will deal with The Witcher in 5 years or more.
We discussed this quite extensively in PM, I think Ciri would make an insanely great main protagonist. Following in her fathers footsteps as a Witcheress and getting involved in quests and contracts. Can also keep the story tied to her parents aswell, cameo appearances or quests. It would make sense because we play as a character we love and all the characters that we get to know over the books/games will be there and Ciri has a healthy relationship with all of them, especially Geralt/Yen. I think it would be fucking perfect, any decision by CDPR that isn't Ciri is frankly a mistake.
Personally I do not wish another Witcher game to happen, but if CDPR years down the line decide to make another one and that it would be Ciri, I hope it would be a prequel to Witcher 3, I don't think she would offer an interesting story post-W3 without the involvement of Geralt and Yennefer.
Thus, a game with her could be more a of a new story, where her main role is no longer "the daughter"
Not that I would want a sequel with Ciri, but I do not think the involvement of Geralt would be a requirement for an interesting story. In Wild Hunt, Ciri becomes independent, and after the ending, she lives separately from Geralt. Thus, a game with her could be more a of a new story, where her main role is no longer "the daughter" - she would have her own new friends, lover(s), enemies, and so on. In the games with Geralt, his parents play no role either, yet not many people complain about that. Not sure if there would be much point shoehorning Geralt&co. into a Ciri sequel for the sake of fan service (which may not even make sense depending on the locations of the new game vs. the different endings of TW3), and if he actually played a major role, then why not just make him the protagonist again ?
even if Ciri does not trust Yennefer anymore for some reason
Like Mrwhitey998 said, they share a bond that even her going independent would not break,