You do have to abide by the 1 keypress = 1 action per game client rule of thumb. The only way you could increase it is to make the key trigger on both when the key is pressed and when it is released, essentially doubling your spam speed. Auto-firing/repeating keys is a no-no and can get you banned.

I honestly don't see how having to press 1 button once every second or so is straineous though.