Not a whole post. Just a few notes. Inspired by Becoming Orcish earlier in the week.
Consider changing around other fantasy races just a little bit.
Zombies are killed by salt. Regular folk beset by zombies can use fire and holy water of course, but salt dries them right out and ruins them. Likewise, mummies crumple like wet paper when they are drenched by clean water.
Gnoles are the evil children of Gnomes and Trolls. They look like humanoid orangutans, live in trees, covet rubies, and like to eat wayward children.
Kobolds are little blue humanoids who live in the walls of peoples' cottages. They wear clothes much like people do, except they're in shades of blue. They go to work and tend their kitchens just like people do. The men are expert miners and the women are expert cooks. If you treat them well they bring good fortune and if you treat them badly, they cause mischief.
The little kobold men consider everything a complicated engineering and construction problem. They will always make the most complicated solutions to problems they can come up with.
This is why dungeons are like mazes – kobold miners can’t seem to just dig straight for the ore.
Little things make a huge difference.