To be a good representational painter–regardless of your style, photorealist, impressionist, semi-abstract–you need to have good drawing skills. When you can draw, you are in control. You’ll start out with a strong image, that you enhance with color. You won’t be struggling to “try” to get it right, you’ll confidently block it in and then move to color.
So many artists are so impatient to get to the color. Before you can effectively work in color, you have to have a firm understanding of the concepts of drawing: form, value, proportion and perspective. Without these, just getting your composition onto canvas can be a struggle.
Also, as painters, our definition of drawing needs to be flexible. Most people think of drawing as something you do only with a pencil. I never draw in pencil. I draw with the side of the charcoal or pastel, or I draw in ink or acrylic with a flat brush. Doing so allows you to block in forms rather than outlines, this enables you to really focus on values, carving out the forms with the various dark, middle and light tones. This is what gives the illusion of dimension, not detail, all the detail in the world will not make something that is drawn incorrectly look right.
Depending on how you want your painting to look, add in as much or as little detail as you feel is necessary. I prefer a semi-abstract look, where details are merely suggested, but the subject is immediately recognizable. Remember to block in the big shapes first, get the proportion and perspective right, and map in your values. Do this with a simple sketch everyday in charcoal and you’ll see the difference in your paintings very quickly!