I finished the Witcher 3 a few days ago. Absolutely amazing story, world and characters! If you ask me now I'm a 100% sure I would buy
Witcher 4 in a heartbeat when it does come out. Absolutely no doubt about it, and from what I read and heard I believe others will as well.
With a franchise so immensely successful as the Witcher, I really can't think of a single reason for CD Projekt Red not to continue and just be done with it.
The Witcher series made this company what it is today. Though I'm sure they will have success with their other projects like Cyberpunk 2077, but just abandoning the Witcher? Not a chance, I can't imagine that. Hopefully they stay with the 3 - 5 years for developing the next one. Sure, sooner would be great but it will have a big influence on the overall quality of the game. But they also can't completely put it on hold and wait too long, if they do there's a good chance they lose too many of the Witcher fanbase besides the hardcore fans of course. Anyway...
Story-wise I'm sure the CD Projekt Red writers for the Witcher series are qualified enough to think of another great journey to continue the series with. It won't be easy, but they have already proven they can do it. Just take the beautiful world with all the interesting characters they've created (based on the books) we now all know so well and began to love (or love to hate) and we want to see much more of.
From what I've seen quoted from CD Projekt Red about the Witcher is that we haven't seen the end of the Witcher series, but it was the end for Geralt as the protagonist. This is what Senior writer Jakub Szamałek said to IGN (before launch):
“I think good stories must have an ending,”
“You cannot extend them indefinitely, and we felt that Geralt has had such an amazing adventure, and his saga is already so long and complex that this seemed like a good point to think about an appropriate finale for the story.”
Geralt “has reached the end of his journey,” but this doesn’t mean it’s the end of The Witcher universe in video games. “The Witcher universe is a very big place with a lot of NPCs, a lot of characters, a lot of places we haven’t shown yet,” Szamałek said. “So, we might return to it at some point…but we think that this is a good place to let Geralt enjoy his retirement and try something new."
Now this was before launch and I'm not exactly sure if they still think the same way after the huge success in sales they didn't even expect. Probably they do, but even if it's really the end for Geralt then he should still play an important part in it. They can't just leave him out completely since he isn't death and him just being far away enjoying his "retirement" with Yen or Triss won't make any sense. Right? He's a witcher for life and he isn't that old! Right, Vesemir? So maybe put Geralt in the role that Vesemir had, just a bit more screen time though, while we can get accustomed to the new protagonist.
But if Geralt is not the protagonist, who can it be?
Option 1: I would say our number one candidate is Ciri. She's probably the most important character (or one of them) in the books and there are so many things I can think of already on how you can continue the journey with her. People saying she would be way overpowered because of her skills, yea if they leave it like it is in Witcher 3 that's true. But don't even worry about that, I trust CDPR to balance it out and make it fun and interesting to fight with her.
Option 2: Another option is to play alongside Ciri as a "newly" trained witcher by Geralt.
Definitely not a totally blank player created character, that really doesn't fit the Witcher series. CD Projekt Red writers will have to give the "new" witcher an interesting history and really introduce us to him. He must be similar in age to Ciri to make it work for the story. I would prefer to play Ciri and the new witcher GTA style: switch between them during the whole game whenever you want. Only lock playing with one or the other when required for the story or in cutscenes. Maybe have the new witcher meet Ciri a bit later into the story and let Geralt introduce them when he's ready. He as Geralt's apprentice could ultimately become his successor in the whole Witcher franchise.
Also, in the books Ciri's future child will one day be very important. Maybe they can do something with that if CDPR wants to stay with the books. There's a mass amount of interesting things they can do if they're going this route which I would prefer.
So much is left to tell and there are so many exciting new paths to choose on this continuing Witcher journey that I'm already excited for number 4. I have a lot of ideas on how to continue, like many of you do as well that don't want this to be the end. Just imagine what a whole team of experienced writers from CDPR can do!
The Witcher series can't end here...