Good thread, lots of good ideas above. Needs can be different for most everyone. All of us have our own issues whether they are personal, medical or where we live and hazards we could/should expect.
I’m also in CA so earthquakes are always a potential immediate threat. Other locations may have tornados. Wildfires here and hurricanes elsewhere are threats, but people may have days to plan or evacuate. EQ’s and tornados are immediate so preps should be made accordingly.
That said, the #1 thing for me is a AAA LED flashlight with a moonlight mode. I use it to read the clock. The clock does not have an illuminated LCD display so a flashlight is needed to see it. I like it dark and an illuminated clock provides too much light. Regardless, that AAA flashlight will get me to a bigger much more capable 18650 flashlight as well as even larger utility floodlight which can illuminate most of the house. Good idea above regarding shoes/boots and broken glass. I may move my boots closer so if needed, I don’t need to walk far to get them.
All that said, I don’t live near one of the major faults so even if the “big one” struck, this house should not suffer catastrophic damage. I’ll survey for damage, make sure there’s no gas leak and then go back to sleep. YMMV