Greetings from Singapore.
I worked as a tourists photographer and also has a small business called Handwriting Analysis.
I am currently doing research into what kinds of stock sells best.
These ideas are from a book called People shots that sell - How to succeed in stock photography. Printed in 2002
The creative options then in 2002 was
1. Cheesy pictures - these are the nice and perfect pictures that depict something like a nice parent looking after a cute baby.
2. Literacy and education sells - use cute pics of children studying or just tools of learning, maybe have parents in the picture. have pics of graduation and successful studies.
3. Lifestyles - cater to different lifestyles for example have pics of senior citizens enjoying their retirement.
4. The winning spirit - representing a winning team or a couple winning over their finances, success over adversity.
5. Global business - different faces of business or types of business
6. Young lifestyles - portraying the teen to young adult lifestyles to cater to their wants and desires.
7. Health care - medical care or wellness - images of doctors nurses and equipment
8. Portraiture - adding a face warms an advertising campaign so simple faces are needed
Future trends may be that the stock industry may be used as the leader of design or advertising rather than just the raw materials so push for the edge.
That's the end of my first message.
Hope to see more ideas