Improved Color Grading Options

What problem do you see this solving?

The Color Balance tool is good but could be better with a few simple additions:

1. Add the ability to input RGB/HSL colour values
2. Add the ability to use an eye dropper to select existing colours within an image.
3. BONUS: Ability to create colour schemes, such as monotone, analogous, complimentary, muted analogous, yada yada yada, etc.

When was the last time you were affected by this lack of functionality, or specific tool?

Every image I edit. I would love to be able to improve the colour grading.