For me its "In the Heart of the Woods". somehow no matter what choice you make in this contract it ends tragically. But the tragic ends make the quest interesting overall. You can view my recorded playthrough.

Whats was your favorite witcher contract?

I hope it's obvious that there will be spoilers here...

One that stood out to me was the one where the man reported his wife missing, and it turned out that not only was he a werewolf and had killed her himself, but that his sister-in-law had basically set the whole thing up. Pretty damn messed up. (apparently the name is Wild at Heart)

I prefer the other one with a leshen - Lord of the Wood. There was much more weather effect tomfoolery. It might be based on the leshen's level. Sometimes they seem to even be able to change day into night and such. I remember the most spectacular fight taking place in the Abandoned Sawmill, but that wasn't a contract, just a secondary quest i stumbled upon.

The contract I remember most fondly was the one that gave me the most trouble - Jenny of the Woods. I know it's one of the most straightforward ones, but it taught me to keep my cool against wraiths and use the dodge instead of a roll as much as possible. Can't wait to face Jenny on death march. I must know whether I improved my skills through the course of the game or just outlevelled everything.

I just completed "cabaret" and am now on "carnal sins" which seems pretty good so far.

As far as "heart of the woods" goes, I freed the night mare tree heart thing cause I didn't trust the crones, but when I went back to the village elder it was a real WTF moment when I saw the whole village in ruins and just him and his one ear left

I also recently played one where a witcher from the cat school murders an entire village except for a little girl after they try to cheat him on his reward I think it was one of the free dlc missions called "where the cat and wolf play" or some thing, I had a pretty difficult time deciding that witchers fate, but in the end decided to let him go

"Woodland spirit" on the skellige isles also had a pretty hard descision at the end.

Skellige's Most Wanted.

I really like how it took the standard contract tropes (Someone in a town drawing a crowd, vague monster descriptions, examining the crime scene, etc) and made things feel slightly off at each step.

As late game DLC, you would normally do this quest after completing countless similar contracts throughout the main game. The quest relies on this knowledge and uses it build a Scooby-Doo/Road Runner like series of traps around the standard contract paraphernalia you've grown accustomed to by this point.

On top of all these quirky shenanigans, It calls back to your many decisions throughout the game with regards to your treatment of sentient monsters. It felt great to finally see some sort of benefit to/acknowledgement for choosing to spare monsters who seemed to be in the right along the way. Finally the quest ends with a great speech by Geralt explaining the complicated dichotomy of a Witcher's work and how he maintains a balance between the monster and human world.

Besides the Werewolf being a glitchy drama queen on my play through with his infinite death animations, I really enjoyed this quest.

Pretty sure I completed in the heart of the woods, and I've never seen that cutscene you posted...

Edit: nvm. I'm thinking of a different quest. It's been over two months and I still haven't seen everything this game has to offer. I love it!