Oh the outline of what's missing is a great idea. Good proofing mechanism and an estimated final word count.

I agree with both you and cleflink that 75-80% done is usually where I'm at during the submission time. But in order to know if the draft is actually holding water, the bullet point outline of what is missing would really help commit the writer AND give the artists something to go by. I think that's a great middle ground because zubeneschamali is right, a lot of people will rush the final version. At least the draft is a wake up call to get your act together : )

And for artists, the rough draft can change dramatically at the end, but at least it gets the image foraging or sketching started and the thinking of the final art engaged.