I don't know the pattern, but you can probably do an i-cord bind off instead of making the i-cord and sewing it on. It makes a beautifully finished edge and I think it does make the edge less floppy. I used it on my sweater if you want to see it.
Here's instructions for the i-cord bind off if you decided you want to do it.
You don't want it tight, but you could try a smaller needle and/or use less stitches for the i-cord. I think I used only two on my sweater so it was smaller and fit in better. That LB Homespun might be hard to work with, but you give it a try.