We all love our colour picker... It saves the top 6 data colours from the themes and even creates some shades. But that might not be enough. If you want to build a design system around the datacolours, the JSON Theme offers the option to create additional colours, e.g. "foreground", "background", "neutral", "good", "bad" and so many more.
All those colours can be referenced by levaring DAX and Conditional Formatting. But creating Measures for each custom colour seems a bit cumbersome to achieve a simple task such as adding a colour to a border... Also, it doesn't scale that well if you want to add those measures to additional reports using the same theme...
My suggestion:
Add the theme colours to the Dialog and show a preview of the colour on the pop up. On Mouseover the name of the colour could be presentet.
