At this point unless you are already loaded up shorting say XLF isn’t a great idea. I’d say shorting individual financials makes more sense. LEH and C are good candidates. To me C is a short to zero, or at least single digits. The easy money shorting XLF was made last year.
Rather than waiting for a cataclysmic event, short or buy puts into the Fed interest rate induced rallies then cover on the way down.
When the Fed has cut to one percent, thats your pre-cataclysm warning. The next shock should be quite severe.