Are you crazy? Don't allow laser pointers incase of accidental injury in the midst of someone firing on 100's of innocents? Really? "No, No don't use your laser pointer, you may hurt someone" while high powered automatic rounds are whizzing by?
I don't think in this scenario, what is "best" from the standpoint of a "Crazy Asshole Killer" is either imaginable for reasonable people or relevant to defending against them.
Of course I realize the next "Crazy Asshole Killer" maybe reading along in this blog with the rest of us "reasonable...
There is no "the answer" there are an infinite number of potential answers and partial answers and answers when combined with other answers might be an effective answer.
In some cases with some people, just like kicking on attacker in the nuts might end an attack and another it might piss him...
In a close up active shooter case of course a ccw is the answer. But in a case like in Vegas this summer there was NO defending unless one had a laser pointer to at least distract the pos. If more than one person (like everyone that went together, as no one goes to concerts alone) was able to...