This book is a decent introduction into working with color magick. However, it merely glosses over one of the most commonly applied color magick uses: candle magick. He focuses on energy work, which is important but the name is misleading as it focuses more on types of energy work than color magick or even theory.
Additionally, I wish he had gone more in depth with shades of colors as the nuances can be effective for practitioners. Another thing that I believe is important to note is the cultural appropriation (for instance, some elements of Feng Shui were mentioned while them being Feng Shui was not). This can be misleading to those who are newer to practicing. [Note: I understand that at the time of this being published we weren't speaking about cultural appropriation but that doesn't give us an excuse to not highlight it now.]