One of the common questions on forums such as this is "What's a good survival knife?". The answer that always shows up sooner or later is "the knife you have on you when an emergency happens". (That's one of the reasons D.R. developed the RSK Mk 1.) Anyway, the best survival kit is what you have on your person.

If it was me, while keeping some evac specific things in a small kit in or attached to your desk is a great idea, I'd be looking at that messenger bag to carry kit items with me all the time. Who's to say you'll be in your office when you need the kit? You may need it during the commute. Get some comfortable walking shoes and wear them to/from work. Leave the good shoes at your desk.

Whatever -- good thread.