There are some really pretty pastel hand dye watercolor prints out there that could work. The ones I'm thinking of have 2-3 colors that are very pale. They add a little interest and still keep it light enough to show off the prints. Take a peek at some of the Hoffman 1895 collection. There are pretty greens, yellows, blues, lavenders. You may have to scroll a little, there are 340 colors.
http://www.hoffmanfabrics.com/SuperS...ssortmentID=36