The game premise sounds really interesting, and there are a lot of cool ideas listed in your design doc! Unfortunately it looks like you weren't able to get to most of it.
When I played I was unable to spawn in as any different creatures, I just spawned as a man with a few different shirt colors, and I didn't notice any difference in gameplay. It would be cool if we could pick between what we play as! The game also seems to crash anytime you die.
I would say the idea has promise and I like how you took inspiration from the theme.