We would like the ability to not only change the call to action button color, but also the text within the button's color. For example, the text color is always white, so a darker call to action button color must be used so there's enough contrast. We'd like to use a lime colored button, but there isn't enough contrast with the automatic white text.

We should allow users to select a color for custom buttons from the list of secondary colors in settings, not require buttons to only use the primary color.

Use case: In a series whose title is a dark primary color for contrast and legibility, the client needs the button to pop off the page with a yellow background. My only option is putting the button background in the dark title color.