You gave us the top measurement only. What pattern did you use?
I did what you are suggesting once and didn't actually quilt it, I tied it instead. Turned out quite nice, as I used a high loft polyfil, so it is one of those cuddle up, fluffy type quilts. Besides that, it took such a short time to tie it (queen sized) as you can tie it at random 8 to 10 inches apart.