Hi Janet -
I developed something similar at my organization - Leader Core Competencies - however, I started at the "top-ish" (in our org, that's VPs and Directors who are one level down from a C-suite executive). Maybe this is the same as your "first level."
They were each asked: "What does great leadership look like (from your peers/from your leaders) at our organization?" From this, I mined seven core expectations/competencies from their own words, and in my own words, suggested 14 behaviors - two for each competency - that build towards competence.
So, to directly answer your question: I used their own feedback as criteria. It works here because "the standard" came straight from them. In my organization, that matters a lot.
What are you thinking you might use as criteria? Good luck in this important work!