I used to have some Rouen ducks. They're basically somewhat heavier domesticated mallards; they look the same, though heavier. Pretty decent layers, actually. I don't care for the flavor of the duck egg as much as chicken eggs (they're too "eggy") but they make amazing cakes.
Mine lived with my chickens for a while. You want mess? At the time, I used an open water bucket, and ducks basically get a mouthful of feed and then go dunk it in the water and eat it together... half of it ends up in the water.
With mine the biggest problem was they were pretty aggressive to the chickens... also, they didn't want to go "in" to the coop at night. I gave up after a bit and then some otters got them. I was only somewhat sad.
With an acre and a half pond, though, you could definitely get some Rouens for the aesthetic you're going for. I've never had aggressive-to-humans ducks and suspect you could breed it out of them by making roast duck out of any that are overly aggressive.