Plagues and other great diseases are important parts of history and some settings. They defy man and may even defy God in their swift and terrible punishment upon the body of society.
My issue with modifying/removing dwarves and elves is that the PC’s may want to play them.
One of the most powerful tools found in the World Building 102b article is the Worksheet. Here is a place to put the settings you might make with them.
A culture has a tradition of wearing animal pelts as a sign of status or job. Carpenters might wear beaver skins, Masons have a moleskin hood to their cloak, Gaurdsmen might have badger pelts. Done to show the culture's respect for nature and how much of nature is equal to each other.