Colour gets simpler and better in Sierra, except of course when it comes to the web. Have you had any odd colour glitches?
colorspace
How to prepare images for colour-critical situations, such as submission to a jury, or for giclée printing.
Working with colour profiles in images, and when to avoid using them.
Colour calibration is important, particularly for displays. Instruments to do this can be costly, but even a more basic method is a big help.
This explains how OS X renders an image for output, to the display, printer, etc., and what rendering intent is.
Explaining colour management for the non-pro user. Why do you need it?
New Wide Colour gamuts should make all colour rendering more faithful. Benefits are greatest to those for whom faithful colour is most important.
How can I convert illustrations in my book from sRGB to RGB, for publishing on Kindle?
The Eclectic Light Company 