To many people, this kind of question is like asking "does anyone know the best kind of string I can attach to the trigger of this here loaded gun?" !!
Then fresh noobies seeing a really simple 'power circuit' think "hey! that's gonna be my first ever circuit I'm going to build!" (not knowing how potentially lethal it could be!)
I believe some cheap mains-powered Ionisers use a similar circuit. And stungun weapons. But the big difference between those and this circuit in the OP, is Ionisers only produce less than a mA of current, which is on par with static electricity. I imagine there are current-limiting resistors.
Maybe you should consider current limiting resistors, or use smaller value capacitors to reduce the short-circuit (i.e. a person attached to the circuit) to a 'safe' (you decide what's 'safe', not me!) current.