Great fabrics, your quilt will be wonderful. I'm concerned, also, about the pattern. It just doesn't look right, too much white. Usually the pattern is the square in a square. There is a LOT of white in the blocks you've made. Try drawing the pattern on paper and coloring in the blocks before you go too much further.
My quilt blocks are large too (already packed away for the summer so can't measure) and I believe they are at least 12". It is my favorite quilt and I'm sure you'll enjoy your quilt too when finished.