The structure of your repository is not beginner friendly because it makes the library installation process more difficult.
Best practices for Arduino library repositories is to have one repository dedicated to each library with the library in the root of the repository. That will permit the popular installation method:
- (On GitHub) Clone or download > Download .ZIP
- (In the Arduino IDE) Sketch > Include library > Add .zip library
This repository structure is also required if you want to add your library to the Library Manager index to make installation and updates even easier.