I think if only the hair looked better it would be absolutely fine. Let's hope it'll look different in the actual show. I mean this video is just a test right? Set pictures and videos always look bad.
It would be stupid to not base almost everything on the video game look cause that's what's everyone have in their mind. It's not like we only had the book and nobody have a picture of the characters in their mind. That's like creating a Harry Potter game with the same characters as in the book but not using the actors likenesses for that. Yes my example is the other way around but it would be the same.
Also, without the games, this series wouldn't exist and nobody would give a fuck about it (and Cavill wouldn't be Geralt). So the viewer base for this product is 80-90% fans of the games, so how could you not base the looks of the characters on the games?
Because CDProjekt has nothing to do with this and that wouldn't be interesting?
I mean, that's some childish gamers entitlement. The Witcher books were well known before the games, it doesn't matter if you had never heard about it. We've seen TV shows adaptations from books that were way more obscure than The Witcher ones.
And yeah if an AAA adaptation of the Harry Potter books is made I sure as hell hope they won't go with the actor likenesses from the movies, that would be terrible. It's fine for official movie tie-ins and even then... the characters in most of the Harry Potter games that came out alongside the movies didn't even look like the actors and nobody gave a shit.