Aside from my hyper-literal take on the words "rock" and "roll," what I was playing with here was minimalism: how simply and economically could I draw and still tell a story? The 16 panels are a basic grid, and most of the shapes are simple circles and straight lines. Drawing the girl, I was partly inspired by Disney's famous flour sack, an old animators' exercise to see how much emotion could be wrung from a featureless bag:
Disney's surprisingly expressive half-filled sack of flour
So, that was fun and kind of worked. I found it worthwhile. I think these types of exercises are valuable in that they make you stop, rethink what you do and why you do it, and consider new approaches. Especially in cartooning, playfulness is important and easy to overlook.