The development will be slow on this game. I think it was years of work before the v0.0.1 or whatever it was was released. He had said from the beginning that he wanted to do open world, you could have guessed it by the detail in the background and the way it zooms. Of course it will take longer than just putting you in front of another witch, but after the "world" is made, expanding it incrementally will take little time.
In short, do not expect fast updates now, or in the foreseeable future. Unless the dev team becomes huge, it's not likely to happen. Do expect the updates, when they do come, to be well polished, top tier.