I have been researching the question of stitch density and have found posts from professionals that recommend more stitching. While the batting recommendations may say every 6 inches, they are recommending that so the batting does not weaken and shred. They are not concerned with the stitches breaking. The more the quilt is washed and folded and used, the more stress there is on the stitches. If there are only a few lines of stitching, each line is subject to a lot of wear and tear. If a quilt is to be used, the more stitches the better. That way the stress is distributed over many threads and the quilt will last and hopefully the threads will not break. The recommendation is semi dense to dense quilting for quilts that will be used by children.
Just google stitch density on quilts and you can find more information.
Good luck with your lovely quilt! Hopefully that baby will drag it around for years to come.