Hi Ladylace -
I'm not an expert, but I have made one traditional wholecloth quilt. If you back looks different from your front, it seems like there are two possible reasons. First, did you use the same thread on the front and the back? Perhaps you like your bobbin thread better? If the thread is the same, the then only thing that I think could make the back look different would be your machine's tension. But if you like both sides, then it seems like it could only be a small difference in tension and, really, it doesn't matter. After quilting, you can certainly decide which side you want to be the front. It doesn't have to be the side that was on the top while you were quilting. If you like the other side better, make it the front and go with it!
My wholecloth used the same thread in top and bobbin, but used different fabric on the front and back. The stitching itself looked pretty much the same on both sides. For this one, I used a single wool batting. When I make another one, I think I'll use a cotton batting on the bottom and a wool batting on the top. This is what it sounds like most show quilters do. I think the cotton batting gives the quilt more stability for hanging flat and I've also heard that it helps to push the wool batting towards the front so you get more puff in your quilting motifs. Then it will matter which side I define as the front!
Nancy