During the preproduction process include your DP, Sound Designer, Set Designer/Props, Make-up/Hair/Costume, etc. These people can offer amazing insights into your script and story. As a "sound guy" I approach things differently; not better, I just have a different perspective; I hear the story rather than see it. As an example, I worked on a short several years ago where the producer was (and still is) a preproduction fanatic. It was a boy-meets-girl story centered on an introverted isolated high school aged writer who never lets anyone read what he has written.
The opening shot as originally scripted showed him sitting by himself outside the school writing in his journal, his friends walk up, he shuts the journal and the dialog begins. I suggested that we open with the sound writing. The DP suggested fading in with an over-the-shoulder shot of him writing in his journal. I responded with we could slowly fade in the school yard sounds, to which the DP said we could pull back to reveal the school yard. I mentioned that then he hears the sound of footsteps, and upon hearing the footsteps he slams the journal shut with a big "Smack!" then looks up, and the Set/Props gal mentioned that it should be a big hard-cover journal and that he should use pencils. The Dp said that we should still just see feet and legs when we hear "Hi Gary", who looks up; next shot reveals "friendly" faces.
All these suggestions gave a lot of insight into the character in a very short period of time. Before we see anything we know that he is a writer. Pulling back to reveal him alone in a corner of the school yard shows that he isolates himself. The approaching footsteps without seeing the other characters provides tension. Forcefully shutting the journal showed that he didn't want anyone to see what he had written, as well as defining specific props.
The conversations moved on to many other details such as making sure that when sitting at a table or in a room Gary should always be a bit removed from the other characters to highlight his self-imposed isolation. Later that would change as his love interest pulled him out of his shell. His room would be full of books and have posters of famous writers. His dress would, initially, set him apart. The Set Designer/Props gal suggested different locations for some scenes. The lighting would be a little on the dark side and brighten as he advances in his new relationship, and the audio ambiences would do the same. All of the visual and auditory clues eliminated quite a bit of unnecessary dialog, enhanced the visual look of the film and provided insights into the characters. After the first preproduction meeting the script was almost completely rewritten.
The point is to allow your department heads to contribute to your project. They are not mindless automatons who do just what you tell them; they are artists who have much to contribute to your film. Take advantage of them.