Yes, I'm familiar with that method of backup as several other apps I use do the same thing (Applied Ballistics, for one).
As you noted, one of the bigger problems (in my mind) with that method is the "warning, all data will be overwritten/etc". What is being worked on is an automatic, cloud-based solution that will function without the user's input at all. You would simply flip a slider to turn on/off cloud-based backup. One of the goals is, as you mention, not simply backing up the data, but rather, to allow said data to be easily shared between multiple devices.
But again, this feature will not be available on the free version.
As for copying the data yourself, it's stored inside the app space, and isn't accessible without a deep technical knowledge of Android, and some specialized software. It's not in regular shared storage - that would require additional permissions for the app to be able to access that, and it's not necessary. In fact, it's poor form in the security world, because if it were in shared storage, any other app couple theoretically copy that file and do whatever it wanted with it. No Bueno.
Hopefully this helps to clarify the direction the app is headed. If you have any other questions or feedback, please don't hesitate.
Thanks!