I think hands down it has to be Angela Walters. Her Machine Quilting Negative Space Craftsy class was the first very Craftsy class I purchased, back when it was still Craftsy. I had been making quilt tops for a while and I had quilted a few on my domestic, sent some out for long arming and I had rented time on the long arm. I needed some confidence to move from the basic quilting that I could do to something more spectacular. I loved her approach. It really gave me confidence to try new things. I love her sayings. And they have become part of my core existence, "Done is better than Perfect" and "Once is a mistake, twice is a design choice." I love her teaching style. It was in her class when she came to our guild that I thought I could really do this, I could own my own long arm and I could do it now, not in some nebulous future that may or may not materialize.