555 Timer - How to quickly discharge RC capacitor
A: To get it to discharge faster add a 330 ohm between the switch output and ground,
to get it even faster also add a diode parallel with the 2.2K resistor. (pointing upwards)
pretty much any diode will do eg: 1n4148 or 1n4001 etc.

B: more simple, the 555 behaves more predictably than most simpler circuits and is pretty simple itself, you could maybe do something with a SCR if the voltage drop is not a problem

C: swap the 2.2K resistor (including the diode from part A) with the 100uF capacitor.