You know, I never really thought of shoes & clothes in our bug out bags, but I really should add some of those. My "quick and dirty" go like you mention for an active shooter is actually my purse. Like most women (and why I conform to this bloody stereotype I don't know - it's maddening) I have snacks, wet wipes, all my ID, money, small sewing kit, etc.
For our big bug out bag we have:
* walking stick (I got a collapsible one so it doesn't take up much space and the handle has a hook designed for climbing)
* first aid kit (pretty thorough - I use this frequently because it has Benadryl & pain killers, which helps me cycle them for fresh on a regular basis)
* hygiene stuff (washcloths, soap, wet naps, tooth care, etc.)
* A couple MREs, a couple protein bars (it'd be one meal a day, but I have enough calories for three days)
* multi-tool/knife
* small folding shovel
* firestarter (lighters and flint/steel)
* saw (one of those chain/cord ones)
* Cylum sticks
* Maps of our area (in those weathertight bags. I can't remember the brand name, but they're fricking awesome)
* pen & a notebook
* compass
* flashlight
* toilet paper
* emergency money & copies of important documents like passport/drivers license
* weather radio (one of the crank kinds - also has a USB port so can charge my phone with it)
* collapsible water jug (designed to be filled before you leave)
* water purifier
* paracord
* Purell
* rain poncho
* signal mirror
I know I'm forgetting some stuff, but without going and unpacking it that's what I know is in there.
The bag is pretty heavy, but there was a method to our madness. It's designed to get us from wherever we may be back to the farm with a specific eye to where Mr. WPW works/where I used to work for distance/number of days. It's in a backpack so I could wear it if needed, but the plan of action if cars weren't an option was to find a shopping cart (when I worked in the town in which we used to live both our condo and my workplace were both right next to grocery stores) and throw anything and everything I could in there.
Also, we don't carry guns in the bag because we both frequently cross the state line into MD and they have some ridiculous notions about guns. It's not insurmountable, but we weighed the pros and cons and likelihood of needing a gun and decided that at this point (subject to change with evolving situations) at this point there are more cons to trying to carry in MD than there are to not carrying regularly. Plus, I don't have to worry about my car being stolen or broken into, which gives me peace of mind.
I do think, occasionally, what we'd do if Mr. WPW & I were somewhere together away from home when the SHTF. We each leave our BOBs in the trunk, so I don't haul it from my car to his if he drives us somewhere. Hopefully it'll never be an issue, but it's something I'd love thoughts on.