simple modification

[Manzo_]

during a peace deal offer, add a shortcut button for "asking as much money as I can with the current peace offer" to avoid multiple clicking on the plus button.

Shift+left click.

thank you sir, didn't know

 

[ThePatriotOfDreumel]

Shift+left click.

 

[GiftGruen]

That's taking 4x or 5x as much money at once, but not the thing the OP asked for. It reduces clicking on the one hand, but otoh it can go too far, making the AI not accept anymore, and there's still much clicking involved if you just want to rob a 100%ed rich nation of money, and nothing else.