A couple ideas for growing and monetizing:
- partner with wedding planners to help grow your community of designers and users - start subtle (prime placement or pro's choice) advertising relationships with magazines, planners, and other communities - expand to include other aspects of the wedding "package", i.e photographers, florists, dressmakers/designers
You might be able to monetize it by, once having the designs completed, making it a one stop shop for doing the rest of the printing too.
However, this could be a logistical nightmare if you've never done printing before, so... tread lightly.
Testimonials for each designer. A design someone posts might be beautiful but what if they lack in the delivery department. Some sort of customer reviews would be nice to have and let people know how dependable they are.
-update Going back and playing around with the site a little more its obvious that your the gateway for each of these designers. By incorporating a rating system for each designer you could be the "Angie's list" of wedding desigers
Good questions to ask myself, thanks for the comment. :)