If the artist's job is to interpret the subject, it's appropriate to depart from accuracy sometimes. Here is an image that could use a little tweaking.
The central strip of shapes in this scene is pretty dramatic. Consider the value spread between the left and right shapes. Could you see darkening the central form a bit? Or lightening the one on the left?
The same kind of adjustments can be made regarding color.
You're in charge of all the decisions.
Look again at the three shapes in the central strip, for example. The middle shape could stand to be a bit more separate from the one on the right, so we could read the space more easily. Imagine the picture if that shape were a bit cooler than the right hand shape, while still warmer than the one on the left.
How about that shadow on the right? What would you want to do with that, in terms of color and/or value?
At what stage of the painting would you make your changes?