Geese are always a lottery, depending on the age of the bird (the old joke about cooking it in the oven with a brick, then throw the goose in the bin and eat the brick). Some duck tastes a bit fishy, depending on their diet. Mallard are okay, as are teal. Not a fan of widgeon. Looking at similar things, woodcock and snipe both taste good and you won't get fat on them. But I'm not for cooking them not drawn and all that!
If you shoot 'em, you should at least attempt to eat 'em. But I think I'm with Shakey Jake on this one. Aylesbury duck is good, but you don't get them flying over you too often.