I think if you use the same color of center sting, the quilt goes together wonderfully. I had been one of the random string blocks until I saw the heartstring quilts. Your idea of sashing sounds great also. I'd love to photos when you get together.
I was also addicted to crumbs blocks for awhile. One year I got on a roll and made about 1000 6" blocks. The leader of my charity quilting group actually gave me a bunch of perfectly matched yardages of fabric, along with a nice pattern and asked me to stopped making the crumb blocks. We have a couple of ladies in our group who make dog beds for the local animal shelters and they take all the small scraps for that. So I don't have to feel guilty about not using all my crumbs. It's been a couple years since I did the crumbs and now I find them tedious. Funny how that works.