I like the intro and using a hand drawn map that was left behind by a previous group of explorers is very clever. When I first looked at your map, I thought the plague doctor was a penguin, and have to admit I was just a little bit disappointed when I read the legend and saw that there was no penguin. I suppose we do have a rabbit man though as a consolation prize.
Overall, I think the the content you have here is weird enough to fit the theme but could be tied together more tightly. I will echo another comment that I think there could be more exposition describing what happened here and what's going on now. It feels like that is mostly left up to GM interpretation. Right now, if I were to run this, I'd probably want to prep notes answering these questions:
- How is Prince Charming is related to the storm brought the black cloud. Does the storm follow him? How do his abilities, mostly combat and mockery, relate to controlling a magical storm? Is he cursed?
- What brought the crows? Do they just like the dark vibes or did they come with Prince Charming?
- What's this rabbit guy doing here anyway?
- What is causing the storm to grow? It just sort of seems like everyone here is chilling? How are they spreading it?
- What is special about this location? Why did Prince Charming bring the storm here?
- Why is the porcelain doll a perfect vessel for raging wind? Is there a relation there historically or culturally?
Then, when I have all those answered, I'd sprinkle little bits of information in various parts of the adventure. Maybe before they get here, they're told a legend about cursed porcelain dolls, mixed in with a bunch of other red herrings so it's not obvious. Maybe on the way, they see someone fleeing who tells them to stay away from the crows and that they defend the evil inside the clocktower. Maybe I 'd modify the presentation of Prince Charming a little bit to include a nod toward the crows and make it feel like they're his underlings/partners in crime. Mostly, finding ways to foreshadow the connections between the storm, Prince Charming, and the crows.