First your directions are great. I don't hand sew if I can help it. Arthritis makes it hard to hold a needle.
I create the tube just like you do.
I attach the top of the sleeve when I stitch the binding on. My bindings are stitched to the back frist and then stitched down on the front so I can see what I'm catching. Then I use my blind stitch foot and fold back the quilt and just catch the quilt backing to stitch the lower edge of the hanging sleeve. I don't sew the ends of the tube to the backing at all.