This may be obvious but: How about putting a large BOB in your car and using it as a central point in your evacuation plan?

Then you could let the other kits aroud it have the function of getting you to your car. For example, your office kit has the supplies to get you out of the building and to your car.

Something basic like: gloves, goggels, dust-mask, flashlight, water and a prying tool(hallagan-tool ??). Perhaps a small FAK and some $$. This of course would depend on your sort of work and if you take your car to work.

As for the BOB's you have with your friends/familie. I would pick just 1 adress, but that's also because of costs and the possibility of replacing stuff.

Good luck!