> it is mainly a question if the game is fun to play.

10000x this. Miyamoto starts with a rudimentary prototype and asks himself this. Sadly it seems for many fun is an afterthought they try to patch in somehow.

When Halo 2 (anniversary edition? ) was released there was also a video on in the game about the development. The point that always stuck with me was "you must nail that 2 seconds that will keep people playing forever". The core mechanic of that game is just excellent.