Hi Matthew,
love it! Probably one of the best articles on design ROI I've read so far. Two remarks:
1) Thank you so much for not including CR and AOV. 🙏🏻 I've encountered so many people in my career who've said things like "Measure UX/design (ROI)? Can't we just look at conversion rate for that?" And that makes me so angry I even wrote an article about it. 😄
2) When I encounter the design ROI topic I usually retreat to this McKinsey study, which gives a pretty good baseline: https://www.mckinsey.com/business-functions/mckinsey-design/our-insights/the-business-value-of-design. Do you know that one? What do you think of it?