Our customer has very specific graphic standards that they want us to follow. It seems that we can override the theme color for just about anything except when widgets are in a widget controller. It would be very helpful to have a few style settings for the widgets when they are in the widget controller:
Widget SVG Icon: Allow uploading of an icon or selection of an icon from a collection and the ability to change it's color (or at least offer white and black color options).
Widget Title Bar: Allow for changing the background color and the font, size and color of the text.
Widget Button: Allow for changing the background color (default, hover, and selected).