However, we can express degrees of "colorfulness" in other ways:
More colorful/Less colorful: These are often used to compare two things directly, like "This painting is more colorful than that one."
Most colorful/Least colorful: These are used to describe the thing that has the most or least color among a group, like "This is the most colorful shirt in the store."
More vibrant/Less vibrant: These adjectives can be used to describe the intensity of the colors, like "The sunset was more vibrant than usual."
More vivid/Less vivid: Similar to "vibrant", this describes the intensity and detail of the colors.
More saturated/Less saturated: This refers to the richness and fullness of the colors, like "The photograph is more saturated after editing."
Remember that the specific adjectives you choose will depend on the context and the nuance you want to convey.