I've had an idea for a while and been mulling over how to tackle it...looked in vain for patterns online so realized it would be necessary to make up my own.
I've mentioned a time or eleven how bad I am at math and knew this would require some of that so I played around with sketches for a few weeks until I felt like I had a workable plan. This week I jumped right into it, and am happy to report that while there was definitely some seam ripping action going on, it was much less than I'd anticipated.
And here it is, the prototype:
I have a small bag picked up at a yard sale years ago but it's not big enough for everything I need to take on trips. In fact, I haven't really seen one big enough anywhere (and I've been looking for years).
Anyway, this one can definitely hold everything I need!
So here's what it looks like folded up from the front (you can't see it, but the hook for hanging it is underneath the strap):