Something is definitely missing. It's nowhere near the "shocking waste of Netflix money" the poster above you ranted over, but it's just.... flat. Up until episode three I had mixed feelings because the whole Witcher world looks more of "A Knights Tale" (complete with **** forgettable pop music) rather than "Kingdom of Heaven". More of a "BBC's Robin Hood" than "Game of Thrones".
It's not even that the Witcher is not "slavic" enough. But it's not fantasy enough. Interiors and sets are clean, ironed, clean shaven, fumigated and perfumed. Furniture is fresh and unused as if straight from Velhadian IKEA. Costumes are... well, way to rich for a fantasy show - not as much dwarfish, elvish and medieval as renaissance or even baroque. Some of the choices are downright bizarre for the genre - not a chain mail in sight, but creased leathers on the army, silks and cross woven shiny, almost metallic looking artificial coloured garments on plebs. It's as "medieval" as Medieval Times restaurants in USA.
Post production is old school British TV like. Colour grading is like Eastenders. It doesn't have film feel, doesn't have the grain and harshness of GoT, instead it almost looks like shot on DLSR's at times. Weirdly, unnaturally lit interiors and exteriors, candles and torches on the walls but it's no "Vikings", there is this indirect light everywhere as if everyone is always surrounded by spotlights following them through forests and dungeons. It looks budget. Even battle scene early on looked like two handfuls of extras running in circles. I thought TV shows had this completely sorted, since Vikings and GoT.
Then there is the acting. It feels like a TV play at times, especially in early episodes every single character except Geralt deliver their lines as if every "fork off" and "up yours" required gravitas and solemnity of Brian Blessing citing Hamlet. There's been more variety in delivery, accents and tone on a single map/city/task in the game than throughout the entire Netflix show.
And then... the weirdest things is.. with very, very few exceptions there is no drama in it. Literally none. Witcher, friends, enemies, doing things. Plots are mostly OK. Fights are nice to watch. You don't give two monkeys about Ciri. You'd rather Jaskier/Dandelion was gone all together. Triss is jarring. When in fever Geralt whispers Renfri, it takes you half an episode to recall wtf Renfri even was, that's how forgettable she was whoever she was whenever she was. The "other main" characters of the episodes are neither interesting, talented, pretty or ugly enough to be memorable. It's all vanilla, all flat.