Well, perfectly might have been a too strong of a word, but there are a lot of great quest mods for Skyrim with good design, writing and great, almost professional voice acting. Sure, it will never be "the real thing" but I imagine if some of those modders that made those mods for Skyrim made Witcher mods and the tools were as easy to use as Skyrims, they would come pretty damn close. And it's not like 100% of side quests in Witcher are gold, either. Some are your run of the mill fetch quests, maybe with a slight twist, and throughout all three games, some quest suffer from backtracking.
My comment about them sticking out is because Skyrim's quest are rarely original or well designed, but in Witcher 3 good design is the norm so they wouldn't stick out as much. Maybe in the other direction, like you say, but not as much.