I use white a lot. When you put your top on the white batting your seam allowances will be much less noticeable. For this reason I use Warm and White cotton batting instead of Warm and Natural. Some white fabrics are heavier than others and yours may have been on the thinner side. But don't worry about seeing some seam allowances they are part of the quilt! Also after it is quilted and washed and crinkled a little you likely won't notice the seam allowances at all.