This was something I had to learn when I started working with color and I'm still learning. What range of values can be achieved by each color? Color can be so deceiving. The actual value of a certain color at maximum strength may look pretty darn dark to the eye but put it into greyscale and the results may amaze you. For instance Cobalt Blue Deep looks like it could go fairly dark but at full strength it really can't. Aureolin yellow at full strength barely makes the midtone range, if at all.
Some artist's like to work 'highkey' and produce very successful results. In other words, they keep their work in the midtone to light range. I'm not one of those artists. I like to use a full range of values to pack a punch, make a painting *pop*, give it pazzazz, whatever you may call it. Highkey artists may use complimentary colors to add drama. I do both. I'm such a drama queen.
Above I've done a greyscale of my painted palette along with a full color palette. I've added a greyscale chart for comparison. The results may surprise you.