I think the more original and different you can get, the better it will look. Look around your house for something you could use. Start watching at yard sales or thrift stores. Think out of the box. Maybe a bakers rack or folding screen? A little dressing table? Anything that you can lay or drape the runners on might work. Function is important too, but with so much to see, you want your booth to draw the people in.
I've done craft shows for over twenty years and I can tell you that the more interesting and different the booth, the more customers will come in. Once you get them in the booth you can engage them with your charming personalty.