Perhaps you could put something together that tells the user what the basic controls are for PC so they don't have to randomly guess which button is the sword/powerup.

2nd: Is there a way to set it so that the games run the attract video after a certain amount of idle time at the menu?

I absolutely second this.
As for the options, in particular, I would like an option to remove the horrible move overlay from the center of the screen AND the useless pause button on the top left.
From the information I gathered I guess these are leftovers from a mobile version, which tells how cheap this conversion must have been.
Also, options for changing game parameters such as language is required.
Currently I am forced to play the game in Italian, and the translation has been probably done with a version of Google translate from 10 years ago. You CANNOT translate 'arcade' with 'portico', for the Heavens!

Chinnico