Creating NPCs in 13th Age

I've been playing with ideas for creating NPCs from 13th Age characters' one unique things, backgrounds, and icon relationships.

I created a chart, inspired by the "Icon Relationship Master Chart" on page 36 of the 13th Age Core Rulebook (or pages 13-14 in the SRD version 3.0). It's a nine block grid--heroic, ambiguous, and villanous icons crossed with positive, conflicted, and negative relationships. Each block offers a handful of seeds for growing NPCs, starting with a character's icon relationships. That seed really comes to life when added to character OUTs and backgrounds.

You can download the chart here. Examples are included.

I wonder, what if NPC creation was part of a "Session Zero" or "Character Creation Session"? Players could be involved in the process too. A chart like this could be really useful.

I haven't playtested this, so I'm open to feedback.