Great topic Andrew!
From the outset, I figure that if I'm going to fish for it, I'm intending to eat it. Therefore I find the fish consumption guidelines in Ontario very useful in planning where to fish, and what to keep. Generally just keep the eaters and let the others go.
I've tried just about everything. At least once. Just to see what it's about.
Channel cats - good in the spring as with mudpout. Whiter flesh.
Mooneye - scaled, stuffed, and in tin foil an the BBQ. Very mushy flesh, but not offensive to eat. Boney.
Ling - actually good. Firm flesh, not many bones, tasty deep fried.
eels (when they were abundant) - very oily, but good smoked. Most are imported from Europe now.
carp - tried to fillet one, but way too many bones. Europeans have them for Easter. It's a symbol of spring. Nice flakey white flesh. Being at the bottom of the food chain, relatively low in contaminants.
minnows - yup, as a kid, we tried cleaning and frying spot-tailed shiners. Good with lots of salt.
Snapping turtle, frog's legs a time or two, sunfish, crayfish (muddy!), even bass is OK
What I won't try is garpike!
Maple
.. 
My fav ocean fish is bluefish, man that's good, I've had ling, not bad. 
