I had meant to respond to your first post when "wonky" was the issue. This particular problem is still very much on my mind as my last quilt had the same problems. I washed it and blocked it on the floor holding it in place with stick pins. It didn't get rid of the problem completely but it helped!
Your quilt is just stunning---I really like the design. It is so modern looking. One of my daughters has requested a quilt and it will have to "look" modern for her tastes. Maybe, I'll do this one. Despite all of the problems, you certainly got this one put together quickly!!!!!!