Another option is “Hutchie” (it can be spelled different ways). This is essentially a tarp, or waterproof sheet with the ability to have ropes tied through the ends to it. You can make various basic shelters with this, and again, they are light and have loads of other uses tactically and practically.

Another potential option is some form of entrenching tool (ET) or folding shovel. You can do your own research for your own needs, but a good ET can substitute or become makeshift (other) tools, like hammers, picks, axes, and potentially a weapon.

Whilst I understand that having a Bug Out Bag has the underlying goal of rescue in sight, do not underestimate the value of concealment. Keep in mind that the disaster in question may escalate criminal, terrorist or gang activities.

Keep in mind that Water is not only used for drinking. People, especially Women, need to conduct hygiene activities requiring water every couple of days. Water is also needed for first aid. Carrying hydration salts/packs are highly recommended by myself. Take note of the amount of water you are carrying, and how you will use it effectively if there is literally no ability to resupply.

My last point, is that you should prioritise and practice your pack. What I mean by that is, store the items you will use first or frequently in places where you can access them in that order. At any one time, you should only have the bare minimum outside of your pack, so if something bad happens, you are able to grab your kit and be mobile in seconds, without having to leave resources behind.