Ok so my mayor?s house originally was going to be a sweets house, but then i realized it was not going to go with my Venice/Paris theme (I?m not actually planning to model my town specifically after one of these towns, these are just inspirations). But I am not opposed to a Japanese-styled town, as japan also has some delicious food (sorry for the generalization) and my town?s based on food.
I think it depends on how you want to design your town around your mayor's house. If you put some Zen PWPs in the area around your house and maybe some of the Asian villagers, like Zucker and Chow from your signature, then the Zen Castle would look nice. But if you don't have much in the way of Zen projects near your mayor's house, I would go for the regular Castle so it doesn't look out of place.