I picked up Van Richten's Guide to Ravenloft and have been reading it cover to cover. This is my review of the book, chapter by chapter. Chapter 3 covers over 30 domains, so I'm posting about it as I work my way through the different domains.
Kartakass sounds like a fun and inspiring place. It's a whole region dedicated to natural beauty and artistic performance. There's an entire settlement, called Emherst, where the entire population is the cast and crew of a huge production: seven weeks of preparation, and then a full week of method acting (or LARPing, if you please.) Throughout Kartakass, music is heard echoing over the lush forests, there is no government to speak of, and everyone has an artistic skill they're perfecting.
Of course, this is a domain of dread, so the catch is that there's a rampant lycanthropy problem. In case you're tracking horror tropes, this satisfies the werewolf trope.
The darklord of this domain is a humble (not necessarily by choice) bard named Harkon Lukas. His eternal torment in Ravenloft is that no matter how hard he strives for fame, and no matter how great a performance, he's always quickly forgotten. Unlike many of the other darklords, he doesn't hold an influential social ranking in his domain. Instead, he's just another performer in a land of artists, and his only power is his manipulative and deceitful charm. Harkon Lukas never achieves his aims, though, and very often his relationships end in his inner beast emerging in the form of a werewolf, and multiple deaths.
In 3.5 Ravenloft, Harkon Lukas was actually a wolfwere not a werewolf. In other words, his natural form was a dire wolf, and he sometimes changed into a human. He was able to control the change, so he remained into human form most of the time. Sometimes, he assumed the form of a human male, and other times the form of a human female. In both forms, he was primarily a harpist.
I don't know why Harkon's gender fluidity was erased for 5e. He gains a daughter (and a son, but he's barely mentioned) in this version, and oddly the art for his "daughter" Akriel Lukas shows a human female dressed in the exact same clothes (boots, hat, blouse, trousers, belts, belt buckle) as Harkon Lukas, holding the exact same violin, in a pretty similar pose. I can't help but think that there was an edit of this section where Harkon Lukas was both male and female, but that at some point somebody decided a rewrite was in order. I cannot imagine why. It's the 2020s, at the time of this writing, and in real world gender is widely recognised as an attitude more than a biological trait, and this book is about a fantasy world where shapeshifters exist. It just doesn't seem to make sense.
To that end, when I run an adventure in Kartakass, Akriel and Harkon Lukas will absolutely be the same entity.
Harkon's greatest weapon is manipulation. To facilitate that, there's a new magic item in this section called Harkon's Bite, which is a necklace with the tooth of a dire wolf on it, and once placed around a player character's neck, it cannot be removed. The wearer of the necklace gains the lyconthropy condition.
This necklace, combined with the fact that Harkon canonically (except not canonically) changes appearance, combined with Harkon's ploys to use player characters to boost his own fame makes this darklord creepy, threatening, icky, and terrifying. Harkon Lukas is that person. The one who's nice and helpful and supportive, right up until he doesn't get what he wants. And then it's werewolf, claws, murder.
I'll admit that I'm not too sure how to work that excellent plot seed into an adventure, unless your gaming group consists entirely of bards who do nothing but engage in performance checks all day. I guess you could send the player character's on some generic minor fetch quests and have their renown rise within the community. Add to that a few late night performances from an artistically-inclined party member, and you can build up a reputation that'll attract Harkon Lukas.
Whatever tact you take, Kartakass is a perfectly lovely setting, and one I can imagine lulling your players into a strong false sense of security. You might even be able to convince them that they've finally emerged out of the mists. They're back on their home plane! Why not spend some time here in Kartakass, resting and recuperating for a while?