Jane can you sew a basic pattern because there are some out there exactly like what you are saying and they don't take long to whip up and you get the advantage of adding what pockets you want and picking some really cool fabrics.
There's a purse I see advertised ALL THE TIME on TV, one of those mini-informercials. It's a long-strapped (removable) bag that holds EVERYTHING. Comes in a variety of colors. I've always wanted to get one. In the commercial, I think a lady is blind-folded at one point as she "searches" for her keys or cell phone or something. Of course, she finds it immediately.
From what you've described, this would be perfect for you.
If I see the ad (which I may very well see since I can't sleep and I'm going to park it in front of the tube, probably, till the sun come up...) I'll come back and post the name of it. But maybe someone else will already know and post it?