Vest or pack or...
Vest? Pack? How about a flybox that fits in your shirt pocket, an extra spool of tippet and forceps in the other, and off you go?
I've always been a minimalist. Give me several dozen of my favorite flies, and a sunny day, waders that don't leak and I'm a happy man. Oh, and now that I'm pushing the half century mark it seems that glasses are a necessity.