I look for modules that have something different about them, such as development of theme or harmony, variety in voicing during the song or interplay between voices similar to call & response. I like funk & light jazz, so you will find some here, such as Funky Trowsers and Soul Kitchen. Also, I like songs that take me on a musical journey of the composer's imagination, songs that tell a story, or songs that have a feeling of poignancy or intimacy such as Stairway.