Re: fly fishable from bank and or wading CFS
This particular belt inflatable PFD (a Stearns - image below) has a small footprint and does not get in the way; plus, its belt substitutes for a wading belt and you can attach accessories to it. If you don't use a wading staff you'd be surprised how much stability it adds to wading in tricky situations. Just be sure to tether it so you don't lose it in hairy situations (the Orvis Magnetic Wading Staff Retriever - image also below - not only tethers, it keeps the staff floating within easy arm reach for emergency grabbing).
On the whole, I'd rather be in Wyoming . . .