It was RobA's tutorial. I dig the simplicity of that tutorial, but I never get exactly what I want. That's when I got the idea of using difference clouds and, doing something sort of like what you do, moving them around and stacking them to create coasts. The only difference is that I sketched out the continenets first and then just tacked the difference cloud bits onto the edges.

Rather than go the whole way around with broken up coasts and islands, I left a lot of the drawn coast exposed. I may go in and use larger (more solid) chunks and fill in the rest with random bits.

Thanks for the feedback thus far.