Ah okay. I always thought Parshendi skin to be described as "marble" due to the patterns being marbled, like a marbled steak or marble stone variances. Their "armor" has always been described as carapace, which as I'm sure you know, is a lot softer than stone. I was thinking their stormform is more like the Essences described in one of Dalinar's visions -the one he has right before the fateful betrayal of Sadeas, where the Radiants say that it wasn't a Voidbringer.
As for Elhokar and the Cryptics, while he may be important, that would also bring the assumption that Shallan is important too, or was before she revealed herself to be one of the Radiants. Pattern was with her when she killed not only her mother, but her father as well, since she killed both of them with Pattern. Also, why can Syl automatically transform when brought out as a Shardblade (spear) and it takes Shallan ten heartbeats to call upon Pattern as his Shardblade form? We know it's Pattern since, one, she doesn't hear screaming in her mind when holding it, and two, it shrinks when she needs it to escape the highstorm tides when her and Kaladin fall into the chasms.