So sad to hear about your losses. Generators are a great stand by to have. If you have insurance you should add your tank/s to the policy for loss of power. We lost power a few years ago and found out that everything that in the fridge was covered by the insurance, after some info gathering we found out that you can cover the tank as well (at no added cost). I now have a generator, battery backups for my vortechs, battery air pumps on standby, and we keep receipts.
What I would do with the live rock is treat it like it is fresh uncured live rock in the tank and cycle your tank as if starting from scratch. Watch for Phosphates as often times after a tank crash you will load up the rocks with them. But other than that I hope you’re able to rebuild better then want you had.