I've been playing around with the idea of providing lighting diagrams to supplement the write-ups of the band portrait/promo shoots that I do. The illustrations would include plan-views of the setups, including placement of the subjects, lighting equipment, modifiers, and so forth.
All drawn with loving care in Adobe Illustrator.
Would this be helpful for you?
Let me know your thoughts and if you have any other ideas for features you'd like to see for portrait shoots.