Even more likely than these; drought, tornado, blizzard, heat wave and power out. Not only likely, but they happen every year. I plan for the most likely events...
IMHO the only smart way of prioritizing is to prepare for the most likely events first. And work from fast, simple and cheap to slow, complicated and expensive.
I told a friend that if he really wanted to save his life he should wear his seatbelt and put a mat down in the shower. He started wearing his seatbelt after his truck skidded and he lost control because he couldn't keep his butt behind the wheel. He drove into the ditch at 50mph and came within 50' of the sudden stop from dead-ending into a culvert. A stop with him going through the windshield.
He came back the next day still rattled from what might have happened. He has worn the seatbelt since then.
I have long advocated a 'start small and work your way your way up slowly' approach. Of course the die-hards loudly declare that if your not preparing for a global nuclear war your not a 'survivalist'. Which is pretty funny because, given the slack-jawed gun-fondling nature of most survivalists, I had never wanted associate myself with the groups or apply the term to myself.
That isn't to say I haven't picked up up a few pointers from survivalists when they were lucid and talking sense about practical matters of survival field craft or first-aid. I pick up pearls where I find them. While ignoring their politics, conspiracy theories, gun porn and alarmist rants. Many of them are good people. Wrapped a little tight and confused about their priorities but good folks.
Funny thing is is that if you prepare for the known and expected challenges your always going to have the rare and unexpected disaster pretty well covered also. Trapped and isolated without power or running water after a hurricane has a lot in common with trapped and isolated because of a invasion of evil two-headed aliens. Either way you still have to eat, drink, stay warm.