This is one time that steam pressing might help. I think your piece looks great, those DWR quilts are hard to get the hang of.

I am working with batiks also for the first time. It sure doesn't behave like other fabric. Mine looked similar to the gathered area and the length that was matched on mine was on straight of grain and exactly the same length so should have been no variance. I am still puzzled over it as I have used this method many times with good results. I am blaming the batiks!