I like some of the already suggested ideas, like Boro/Kantha, and stripes (well I always like stripes!)...
I'm also thinking that a "Lovely Lingerie" contest would be nice; could be anything worn underneath a garment but not on it's own, so bras, camisoles, slips/petticoats, panties/knickers, etc.
Or what about an "Awesome Accesories" contest where the person would have to show the outfit that the accessory/accessories were meant to coordinate with; could be hats, bags, scarves, or even fabric jewelry...
I'll add more as I come up with ideas