I love my light color Sennelier pastels for glazing. For example: the texture in the sunlit sand was created by very lightly grazing the side of a peach colored soft pastel over the darker base colors.
As promised, I will try and add a little bit of information about my work with each post. For "Last Light of Summer" I wanted to show a strong contrast of light and dark so I used Terry Ludwig darks for the top of the light and the shaded foreground. If you want rich, strong dark colors, you can't beat Terry's pastels.