I understand Polish a bit (especially the "bad words"

). Have to say that if the translation were faithful, Korgan would've had a heart attack.
What remained in the English version after trimming the rough edges is indeed bleak. Still, I doubt the original dialogues were well-written either. Obscene language might add some distinct flavor, but the dialogue content is the most important part. And that is what sorely lacking, imho.
I don't have a problem with the Witcher's "mature" aspect. But the mature aspect does not elevate this game above its overall mildly entertaining level, sadly. It's still a rather average game; I would say more like action/adventure than RPG.