What fish have deliciously edible skins?
The skin of all the small fish I have tried is delicious. I have never tried, e.g. tuna skin, and I imagine that it is too tough and I also wouldn't eat shark skin.  Back when I used to eat fish, I always ate the skin, and found it to be the best part. Beware, though, as while the skin concentrates the deliciousness, it also concentrates the mercury and other contaminants, so you may consider limiting your intake.