key4unc

This is Kaye Woods' 6-hour quilt technique. I have made several of these and have yet to make one in 6 hours. This one took almost a week--mainly because there are directional fabrics in this so I had to plan carefully. Also because I don't have a serger so I have to double-stitch my seams to get them flat. OK---'nuff about that. The question is whether I should add another round to this quilt. It currently measures approximately 40X48. If I add another round, it will measure approximately 48X56. The fabric I am showing as the final round is the only fabric I have in my stash that would work with this--and I'm not willing to buy more fabric. Also, I don't have anymore of the blue dottie fabric that I used as the backing (see 2nd pic). So if I add another round, the back would have a different fabric on this last round. I have enough of the leafy fabric in the 4th round on the front to use that on the back. Or I could use the bubble fabric that I'm thinking about using on the front and repeat that on the back. Oh, BTW, this will be a charity comfort quilt.

1) should I add another round to make it a bit bigger (if you answer no to this question, you don't need to answer the other questions)
2) if you answered yes to the previous question, does the fabric I'm thinking about for the final round work with this quilt?
3) if you answered yes to the previous questions, should I use the leafy fabric on the back or should I use the black bubble fabric that will be used in round 5 of the front