If I was going to make one suggestion it would be to use a finer stitch. More stitches per inch, a smaller awl hole, and a finer waxed thread.
20 plus years ago when my wife and I were serious ML shooters I made a fair number of shooting bags for people. I learned quickly that by splitting the common artificial sines into 1/4 or 1/2 the size and making stitches 1/5 inch of so I got a better looking stitch line.