I have hunted ducks from small boats and from canoes along with wading for them. The decision would be which one is more comfortable for you.
For comparison.....The Pirogue will be narrower then a standard canoe but the skiff will be winder then a canoe.
I am making the Bayou Skiff right now and it would offer a lot more stability then a pirogue. In all truthfulness the Bayou Skiff is a wider pirogue in the same basic design. Both boats are a flat bottom ( shallow water) and with a good degree of rocker in them. It will weigh more then a pirogue simply because there is more wood in the construction of it.
It comes down to width , stability and weight depending on which one would suit your needs better. Also something to consider is what you would be taking with you , the shotgun is understood , and would be no problem in either , the amount of decoys needs to be considered , waders , a thermos full of hot coffee , a retriever or a buddy and assorted other items.
Would you be shooting from it and moving around a lot , then something with stability. If you have to carry or drag it into small ponds , then the weight.
Only thing I know for sure at this time is the Bayou Skiff will take more camping gear then my standard length ( 15 1/2 feet) pirogues. I know that from comparing them in the shop. If the length is a consideration.....The Bayou Skiff is actually 13 feet 9 and 1/4 inches in length and a foot wider on the beam.
I hope this helps to some degree.
Chuck.