I can really understand your disappointment if your quilt has come back and it isn't how you dreamed it would be then you are naturally disappointed......but that's where I think the problem may lie...if you don't relay what the end quilt looks like in your head to the LA quilter then you will always be disappointed.
If I were ever to send mine off I think I would draw a simple drawing of the quilt and in pen show what type of quilting I would like.... even if it was a useless drawing hopefully it might give them a much better idea of what you want.