Personally, I do think that WASD is more precise than point-and-click. When I am playing Diablo (point-and-click movement), I have a hard time getting my character positioned correctly to avoid AoEs that are telegraphed on the ground. When I am playing Factorio (WASD movement), I have never had any problems getting my character where I want him to be.

Python has a builtin argparse module. You should use that. It does all of the heavy lifting and logic for you.