Your stockings are beautiful and I would definitely use thin batting and quilt the front and back. We are using the stockings I made way back around 1981 (the colors of reds and greens I used are now back in style!!) and I made every mistake anyone could think of and they still look great. I'll try to make my story shirt.....
I began quilting in 1979 when I was pregnant with my son - we did everything by hand at that time. I found a stocking pattern with appliqués on the front - with a log cabin type pattern around. No problem - but I was not the most experienced sewer (I hated home ec). Not knowing squat about machine quilting it purchased the highest loft polyester batting I could find (still have the leftovers). Managed to,get through sewing the fronts - the machine appliqué is appalling but could be way worse. Couldn't find prequel red fabric for the backing decided to quilt it myself - here's where things really go off the rails! I cut out the stocking back fabric and a same size piece of batting - then I n my great wisdom I figured that the quilting stitch was small so I set my machine to the smallest stitch it would make, marked off a diagonal grid (that was good) with chalk and proceeded to stitch on the lines never noticing what was happening to the side of the backing. Getting the high loft batting under the machine foot was a pain but I managed to do it for the 3 stockings I needed. There is a way to sew tHe stockings together with the lining that is really easy - can't remember his to do it but this is where I noticed that the backing was quite a bit smaller than the front. The lining ended up stuffed in the toe as it was the size of the front and way too big for the back - didn't even have to finish sewing the opening closed as there was so much fabric. Christmas wouldn't be Christmas without those stockings and my husband and son do not know how I messed up - sometimes beginners go really wrong but everything works out in the end. And I haven't made a stocking since!
Someday someone will really wonder .......
Sandy in Mooresville, NC