When I first visited the official q2a market, I thought there is all plugins and themes by all users but it was only by the authors of q2a so, its kind of weird and not creator friendly. I'm not a theme or plugin maker, however when I need something I want to see everything in one place just like playsore or app store (as a normal user wish I think).
So what I recommend you is to change the q2a website script to an open classified website (something like this http://open-classifieds.com/
) so that anyone who create something post it there and sell it. User can find anything easily and a bigger q2a market.
Thanks for reading.