A few settings to globally adjust the brightness and saturation of the current color scheme (any scheme) would be useful.
This would allow users to "tune" any color scheme to their tastes without tediously editing RGB color values in the scheme files. Many color themes may have a very pleasing palette, but just be too bright or too washed-out for one's tastes.
I'm thinking something like:
"background_brightness_multiplier": 1.0,"background_saturation_multiplier": 1.0,"foreground_brightness_multiplier": 1.0,"foreground_saturation_multiplier": 1.0
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