In theory, it could be feasible to connect to another map provider. But I'm unsure other providers will gives as much as information as OpenStreetMap can.
I have chosen OpenStreetMap because other providers are very costly to get terms that allow reuse, and I could not afford to pay for everyone use.
An option would be to contribute to OpenStreetMap to improve details on our area. It’s quite accessible with the web editor (called “iD”) : you have an aerial view, and then you have to point and click areas. I’ve planned to add a page in the wiki to explain which elements are used by the generator and how you can map them on OpenStreetMap.