Color Palette

That sounds a lot like linked text styles which is already available: https://helpx.adobe.com/premiere-pro/using/text-styles.html

I like the idea, but I was thinking more along the lines of the "swatches" from Illustrator, but directly integrated into the properities panel.  For example, if you're working on a text layer in Premiere Pro and need to make a background and instead of using the color picker, you can pull from your saved favorites.  This method feels kind of clunky to me.

Perhaps something like this would help?

https://creativecloud.adobe.com/cc/discover/article/five-ways-to-build-a-color-palette?locale=en