I made a few more (three to be exact) until I felt like I had a good solid process, and I did list the three prototypes in my etsy shop at a reduced price ($15). The regular price on this size will be $22. Before I could get the first one listed at regular price, I sold two!
My next plan is to make this in a larger size for ereaders and perhaps iPads. I also plan to make them more in a regular wallet style - large enough for unfolded paper bills, a couple of credit card slots, etc.
Let me know if there are options that you would like to see, and specific fabrics also!