Thank you very much for your feedback! We are currently considering and discussion on how to achieve a better learning curve to the game by procedurally slowly introducing new material variants.
Each material actually has a different purpose! The buttons trigger all the TNT currently visible, while the TNT by itself does nothing. The TNT simply explodes and destroys adjacent blocks. There are also a few different properties to wether they fall or not without a connection.
Yeah we really need to improve that!