Sometimes I am a Purist. Other Times I Play.

The mood of the approaching storm was better shown when I played with the contrast and colour of this image. Often the sky's definition can be lost to brightness. Recovering that definition can be done with various presets or playing with individual controls within Lightroom (or Photoshop). Changing up the colour can also enhance the image, depending on the feeling you are going for in your shot.

No matter, you still need something good to work with. Composing most or all of your shot in-camera is still the best way to go. What you add from there can in fact add to your image. Careful, as it can also take away from the shot. Finding the right balance requires thought and insight into what you want to say or show.