Few thoughts.....
Cooking: We too have the gas grill (propane). Large cylinder. usual grill style with side burner. Could be used multiple ways.

In addition we have a an old Coleman 2 burner camp stove. White gas or small propane canisters (with the adapter). Can also be run off the large cylinder.

Last resort is our old MSR Whisperlite International. Single burner and can use white gas, gasoline, kerosene, jet fuel.... almost everything but urine.....

Keeping of food.... after Irma, we did the usual run through the refrigerated food, then the frozen. Then we started in on our supplies. One thing we DID find out.....Our chest freezer.... the lift the lid style.... maintained refrigeration temperatures for 4 (or 5) days and looked like it'd go for longer! Even with opening it numerous times! Enough large blocks of 'ice' (frozen bottles of water) kept it cold for AWHILE! It stayed below 38 degrees F! In Florida! Better 'conservation' of cold (less opening) and it could probably go longer. Plan was and is to move (refrigerator) things into it on day 2 of an event.