Have you guys looked into the Jungian Functions at all? You can dig way deeper than doing an inventory.
This is Jung explaining the Functions, it's super dense but definitive:
Classics in the History of Psychology -- Jung (1921/1923) Chapter 10
All of the MBTI books I've skimmed have been pretty bad by comparison.
Here's a visual chart that shows the functions of all the types:
I don't like how MBTI classifies the J/P distinction,
here's a good post about it.
As an INTJ, my dominant Ni is a perceiving function, so it's kinda confusing that I'm classified as a J via MBTI.
Lately I've been in the habit of trying to decipher the functions of all the people around me. It's a fun mental exercise. Unfortunately I live with 2x ISTJ and an ISFJ =(