After-hours access was one of the specifics I was wondering about, which would negate your BIB kit back at the office if train service were suspended till the next day.

I've had to wait at airports, just sitting wherever you could plunk yourself down and lean against the wall in the terminal when all the seats were occupied. Too bulky for a commuter kit, but something padded to sit on would make life easier on the tush. One of those closed cell kneeling pads for gardening would've been very helpful. Not sure if anything inflatable would provide enough cushioning to sit on comfortably for long periods.