Snack collection at Starbucks

I got together with my dear friend Iva for some sketching and chatting at our neighborhood starbucks. I hadn't seen her in a few weeks, so talking to her was more important tonight than doing challenging sketches. I picked a subject I could see from where I was sitting, and just went for it. I started directly with my dagger brush and added a few pen lines at the end to bring some clarity to the sketch.

I am not entirely sure about the background. I didn't want to leave it completely white, but I didn't know how much, if any, detail I should put in the background. Any suggestions?