Promotion rules-free the prisoners!

I would suggest a small change. Many sports have made small changes to the rules in order to make them more spectacular. Reading the rulebook it says that the pieces are "captured", not "eaten" or "killed", that is, they wait for a soldier to free them. So when a pawn arrives at the end of the path he "frees" a captive. So there cannot be two queens (of the same color) on the chessboard. Each king, even sultans, has only one queen.

I'm pretty sure that used to be the case (at least in some areas); it got changed with the more modern rules.

It is not true that the rules of classical chess have not changed over the centuries. The initial move of the pawn 2 squares has not existed since the beginning of chess