I don't know if you read the stream I started titled "First Aid Prepardness" or the stream Tango61 started about first aid (sorry, I don't have the title...) they were written in the winter/fall of last year. The debates about risk vs. reward were polite, but fierce, and may cut to the core of what you are getting at.
As for the actual bag to carry the stuff you decide you need in it, I'm looking to lighten the box store case that mine is currently in to something equally convinient but lighter. It's a marginal change that I'll probably pursue next fall. It may knock an ounce or two out of my pack...