Eshonai's only canon picture is the chapter header icon in her PoVs. She looked like a tank!!! And because I was inspired by the Predator movie series, I draw her as huge and physically imposing relative to the other characters. But she still has a human-like face that isn't fully monster, even in Stormform. I tried to make it expressive, but clear that she's not human, hence the creepy glowing eyes.
This is my impression of a chrysalis and gemheart. In my imagination, they were giant glowing, roughly faceted chunks of crystal that had mysterious flickering lights coming from the inside. And the "violet ichor" of chasmfiend blood was like a goopy slime that dripped out when you pulled the gem out of the chrysalis. Who knows, maybe it's really the texture of purple ketchup.