which is the best piece in chess?
totally agree
The question is no real question, since everyone can figure out the following truths:
_ While the King is the most important piece, the Queen is the most powerfull.
_ It happens the Knight gets more important/powerfull than usually, due to tactical patterns related to its unique abilities. A well placed Knight, protected by a pawn, can prove more powerfull than a Rook, for the rest of the game.
_ The combo Queen+Knight proves overly dangerous and painfull to counter.
_ Ultimately, in some given positions or situations, a weaker piece, even a pawn, can become the center of the attention, when the outcome of the game depends on it. Any piece able to deliver a one move checkmate is the star of the moment.
etc.
Otherwise, we can also waste our time discussing about the shape of the Earth, ignoring the already axquiered knowledge about it.