Want opinion on witch Genre I should wright my book

Hello everyone I'm not sure what this is used for but I was wondering I just finished my first book you see and I'm writing my second one and I want to know what sounds more intresting the book is about japan during the 1500-1600s and I was wondering would it be better to make it fantcey with the japanies Mythos or keep it realistic ether way I have a lot of knowledge on both so I just wanna know people's opinion