I just finished a denim/corduroy quilt for my son and tied the centre panels using decatur knots (gives a nice cross stitch finish) and I used crochet cotton. Looked pretty nice and then I ditched the borders with my vintage machine (takes pretty heavy fabrics). Your project looks really pretty....please show us when you are done.

1 2 There is a method to tie without a knot. you use 4 points 1 2
3 4 3 4 you can use thread or yarn
Thread goes down on #1 up on #4, Down on 1 up on 2 down on 3 and up on 4 . There is an x on the top and a z on the back side. leave a short 1/2 - 1 inch on both ends. This prevents the hard knots when cuddling with a quilt. Will not pull out.
The numbers should line up with 1 &2 above 3 &4. When I posted they shifed so I added another set and hope they stay lined up. This works well on corner of blocks with each number representing a corner so you can miss the actual seam if you go 1/4" . PM me if you have questions.

Thanks for your sharing your method Spice.....I will give this one a try....I like the flatter profile tying methods. I often use heavy fabrics so machine sewing isn't always possible.