It is a little hard to see the stitch definition in the darker hats in the photos, but they stand out in person.
The following pictures include a few hats with traveling stitches. A little more complicated than knit and purl, but they are really beautiful.
It is amazing how much variety there is in hats in the above pictures. Even hats that use the same pattern look different in various colors and stripes. It's one reason I love to knit hats. You can experiment with color and design without investing too much time in a project. You can also memorize one pattern and knit it repeatedly, but change the color and it looks different every time.