I agree that good photos are so important. I regularly see what are almost certainly lovely items, where the photos are really poor - stuff like busy backgrounds (and often no thought for a background at all - we don't want to see their kitchen and the washing up!), or items obviously displayed on a crumpled duvet on the bed, or even photos where the picture is sideways - all those get used as the main photo... If you are taking time and trouble to make beautiful items, then you must also take the trouble to get the absolute best photos you can.
There are free pieces of software, which enable you to edit and improve your pictues, even if taken with a simple camera (try Gimp, it's similar to photoshop, but free!); there are lots of tutorials and bits of advice out there on the Internet (and at Folksy - see the blog!), on how to improve the quality of your photo-taking.
I've just invested in a new camera, which I plan to use to upgrade the photos in my exisiting listings and to take much better pictures for new stuff too.