I enjoyed it a lot. I have read a couple of the books its based upon (and played the Witcher videogame series) so it was always going to kind of be in my ballpark anyway, but it was a genuinely pleasing experience.
Not flawless. Some of the visual effects were somewhat lacking (the dragons in the middle of the season for example), but the fight sequences were great and casting broadly very good. Henry Cavill has the ridiculous gruffness of Geralt of Rivia down perfectly, and I found watching the progression and growth of Anya Chalotra's Yennefer fascinating. She works far better than I expected. Pretty happy with that.
Joey Batey's Jaskier worked brilliantly. And yes, for those confused, that is Dandelion the Bard. He has alwatys been 'Jaskier' in the original Polish. Which I belief translates as 'Buttercup' rather than Dandelion, but either way is what they've opted for here. The 'Tip a Coin to your Witcher' ballad will get stuck in your head.
Not 100% sold on Anna Shaffer as Triss Merigold. I think such an important character from the books arguably needed a stronger actress. But, to play devil's advocate here, we haven't really seen very much of her so far. I only know her as having been on Hollyoaks a long time ago. And it's hard to say with soap actors if they're any good until they're given something to properly work with. Maybe I'll change my mind once we see a bit more.
I know that others who have chiefly come in contact with The Witcher through the games may (and have) rante(ed) that she is not a Caucasian redhead. But I would also point out the games differ from the books on this. In the novels she is simply described as having Chestnut brown hair and blue eyes. The latter may not be true in the TV series, but the former is. I've no problem with that.
The main complaints I've heard of people about the series is that some have had difficulty following it. It dies play with time, you aren't seeing a sequence of events from point A to point B. Some people found this to be confusing. I do wonder though, given that non-linear time narratives have been commonplace in popular culture pretty much since the late 90s why so many people still find these confusing? I twigged somewhere around episode 3 that something was going on. I didn't find it hard to follow.
The books likewise dot about a little in terms of timelines. It's not a big deal in my book.