We did a batch of pekin meat ducks once, and vowed never again. They were SOOOOO messy, and ate / wasted loads of food compared with the amount of meat on them.
I'd say get a prolific laying breed like utility Khaki Campbells, supplement those with one or two that are fun to have around (say runner ducks for comedy, or Welsh Harlequins for beauty), and then keep meat chickens to eat instead.