I think I might just go with all females, as I don't really like the idea of eating fertilized eggs (and it would be soo tempting to incubate them!).
Would it work to get one WH and one Ancona and one mini appleyard?
How did you guys get your ducks? I could only find one hatchery that even sells the WH, but the minimum order was 10 so that they stay warm... I don't know if I could find anyone who would want 7 ducks if I were to split an order.
As for the coopers, I may just build an enclosed pen in part of the yard (as I will probably be building one for my button quail and the area under the deck would likely work fine for part of the day) and only let them out in the yard when someone is home to keep an eye on them.