Always the most painstaking decision for me is how to quilt the quilt.
In addition to the ideas mentioned above, sometimes I take a motif from the fabric. One time I was doing a doggie quilt, and so gave each block a simple bone-shape in the middle. I made a template for the doggie bone shape, but then discovered that it was easy enough to FMQ .
I also find star shapes linked with loopy-de-loops are fun. All different sizes. That helps me loosen up to tell myself that the idea is "all different sizes."
Stencils have also helped me. I use either chalk (white on dark fabric and vice versa) or Crayola Washable Markers (which I tested on--and rinsed out 0f-- a sample scrap block just to be 100% sure for my peace of me).