I'll just come out and say it. (SPOILER ALERT)
Even though I liked the game overall, Witcher 3 is one of the most overrated games I've ever played, with all the praise given to its admittedly exceptionally good writing, characters, choices, and world-building covering up the fact that, when you remove all that, the gameplay loop and the like is only average at best.
Like, whenever I hear people sing the praises of it in videos calling it the greatest game of the 2010s and all that, almost all I hear is them gushing about the story and characters, and how superbly written every single quest is, while suspiciously making very little mention of the fact that when you actually have to play them, you're basically going over the same exact mission structure over and over again.
Not to mention that I feel that the game's pacing is a huge issue post Battle of Kaer Morhn. Seriously, that mission has all the feel of being the final one, or at the very least, penultimate one, so I expected the game to end pretty soon afterwards. Nope, there's still 10+ hours of game left to go. At this point, the game's momentum comes to a screeching halt as you now have to do all these other missions before the game actually ends, and there's no new locations or anything either. It just feels incredibly awkward and deflating.
Again, don't get me wrong, I still think the game is good, purely for the writing and all that. But unlike everyone else it seems, that simply isn't enough for me to overlook the issues IO have with it's gameplay, mission design, and pacing.