Very nice quilt. I like the color combination and pattern.
As for batting, it depends on the final look you are going for with your quilt. If you are looking for the antique, crinkly look, use an 80/20 cotton or wool batting. If you're looking for a look similar to today's comforters, go with a 100% polyester batting. There are also bamboo and silk battings available, both are a more expensive though. Each quilter has their favorite and there are many good manufacturers of batting, Warm & Natural, Hobbs, Fairfield, Mountain Mist, just to name a few.
Another factor is loft and whether you want your quilt to end up thinner for year round comfort (low loft) or winter use only (high loft). Lower lofts are easier to quilt with both hand and machine. Higher lofts lend themselves toward machine quilting only. The thickness makes hand quilting more difficult with high loft batting.