You could also devide them between situations:

- Home-emergency bag:

Bag with stuff like digital stored photo's, important documents, spare cash, etc. For example when you have a house-fire. This is a short-term emergency.

- Disaster-emergency bag:

'Traditional' BOB for stuff that is used for example with large floods, hurricanes, earth-quakes, etc. when you don't know when/if you'll be coming back.