Why can't it be both? We can get a lot from wider map size to different lands. Kovir & Poviss, Lyria & Rivia and others. I myself would love to go back to the start, as I have stated before, it's now time to go back to the beginning "The Butcher of Blaviken" before the fall of Cintra. We only get a glimpse of the books from the first game in the opening cinematics.
We can also use fluid like controls, the speed and ballet type of movements as described in the books. While it worked for Geralt in some points, it hindered him as well.
TW3 is a beautiful masterpiece with the colors and locations, but the storyline and sub-plots left more to be desired. I will direct your attention to what I think the game felt like to me (it will also age me). "Raiders of the Lost Ark" is the finest example of the direction I am taking you. "Indiana Jones & The Temple of Doom (Horrendous piece of garbage that gave the world a new rating code)", "Indiana Jones & The Last Crusade". A perfect end to the storyline of Indiana Jones (stay with me, I am getting to my point).
After years of hounding Stephen Spielberg & George Lucas for another Indiana Jones movie, they created something that is almost as bad as The Temple of Doom, "Indiana Jones and the Kingdom of the Crystal Skull" Here's the point to it: The last Indiana Jones movie was just a way to shut up the fans, all it did was enrage the fans with the horrible storyline, sub-plot and action. See the connection?
CDPR did a fantastic job with the open world aspect, the looks of the characters. But the storyline, sub-plots and action was watered down. While it gets a rating grade of "M" in the States "18+" (or is it 17?) elsewhere for the amount of violence and language, they watered down the "Adult Situations" is the term I will use, in which they had amped up in TW2. We have 2 games with Triss as the love interest, only to get Yennefer in the last one because this is what the lore fans wanted (there are other lore items that were also needed. some made it, others did not). And no matter what, I still can't choose Yennefer over Triss. But let me say this one thing, I have 2 copies of the game, XBox One and PC. I walked away from the XB1 version with me choosing Yen over Triss, and that won't change, but for PC, Triss will win every time.
What I am saying in a long typed out post is that, CDPR gave us their word that there would be a 3rd Witcher game. But as time passed, they were trying to meet deadlines and make money, and so they gave us "Indiana Jones and the Kingdom of the Crystal Skull". After 10 years with Geralt, they wanted to move past him as quickly as they could to make other games. While I can't fault them for wanting to move on with something new, I can fault them for one word "Soon".
I don't know if I could play another Witcher game without Geralt, I just don't know. I do know that I would play another Witcher game if it started back to the beginning, following the cannon of the Witcher Universe. After reading all the books, I love that cannon. Don't get me wrong, I love the direction CDPR took us on, 5 years after the disappearance of Geralt & Yennefer. But maybe it's time to get back to the basics.
I know I will catch flack because I want to go back while others want to continue moving forward, but it is, what it is....my opinion.