I agree with the others. they will love it. If you think about it, if they don't quilt, they more than likely will not notice mistakes only you will because you know they are there. I made a double wedding ring for my daughter who got married in Jan. I started it and changed patterns several times before i finally ended using Eleanor Burns applique pattern, which I didn't want to. I wanted to do it the old fashioned way but I was running out of time. Yes, there were mistakes but noone seemed to notice, unless I told them. lol
You might consider appliqueing a square block over the corner squares. I'm sure it is beautiful, though.