Not sure I can agree on your opinion on "Noncore Doctrine" or why you divide "Core" from "Essential" for that matter...

"Every Scripture is God-breathed and profitable for instruction, for conviction, for correction, and for training in righteousness..." - 2 Timothy 3:16, Berean Literal Bible.

Anyways, I never fully understood the meaning of the metaphors of "bruised reed" and "smoldering wick" in Isaiah 42:3. ^h9w website explains it well - at least to my own satisfaction:

https://www.gotquestions.org/bruised-reed-not-break.html

I thought you might be able to plug it in somewhere on that scale of importance.

"...not one jot or tittle..."