Hmmm, I would think that the pen section for exotics (you mean wild?) would have much more complicated design criteria, and the domestic ducks would just need a standard secure pen.
I think there have been some threads about designing pens for wood ducks and others. Let me see if I can find some links.
The ornamental ducks need much smaller wire than domestics do, they don't use houses, and require multiple hung specific nest boxes to pick from come breeding season. They also require more space in the pen to happy, healthy and potentially breed. 10' x 10' would not be adequate for a bird who perches, flies and swims. The larger the better allowing space to spread out, or you risk fighting.
Also read up on which breeds do well together, some aren't good to house together unless you have VERY large aviaries.
Well you can't have any of those ducks mixed together on the domestics (blacks, call and mallards) they will cross breed like crazy and are very messy.
The mandarin will need their own pen seperate from these and you need at least a 10x10 space per pair.
and for the Canda geese.. first remember they are one of ther permited birds and second I would put them in with any ducks.
Remember, we LUV pictures here at BYC. Keep us informed.
I am building a drake pen myself this weekend. My guys free-range, but I am forever suffering from too many drakes per duck. I plan to build shelter from wooden pallets. The location is under pines.