Could you make two smaller quilts with the two different sized strips? Maybe mix in some other fabrics to get to the right size. I remember my mother turning a "mistake" quilt into a dog bed. It was so pretty and the dog loved it!
By the way, your avatar quilt is really beautiful. Anyone who could design and make that has a true gift, so I'm sure you can make something wonderful with you strips (even the world's nicest dog bed!)