Store predefined group colors as dict?

Could we change colors for groups from being defined by an array of colors to being a dict mapping from the relevant key/ category to the color? I would find this more intuitive, and much easier to modify. Plus tools like seaborn can accept dicts directly as a palette:

import seaborn as sns

iris = sns.load_dataset("iris")
g = sns.FacetGrid(
    iris, 
    row="species", 
    hue="species", 
    palette={"setosa": "red", "versicolor": "green", "virginica": "blue"}
)
g.map(sns.kdeplot, "sepal_width").show()

Start by locating the existing group-color definitions and every place that consumes them, then check how the current array order relates to group keys or categories. Done means colors are represented by a key-to-color dict throughout the relevant plotting path, with tests or examples covering the new form.