You have enough feathers there to tie a bunch of flies. Of course the Pintail flank can be used in lieu of mallard flank, likewise the Drake GW Teal. The widgeon flank makes good looking flies as well.

I got a Ross Goose about 5 years ago. I plucked it and saved the feathers. I dye a few of them now and then to tie various flies, usually steamers. Left white they can be uses as wings of steamers.

I take the belly feathers from the drake GW Teal and use the m as a single feather wing laid flat along the back of the fly. I usually use two feathers one on top of the other as it improves visibity of the angler. You can also use the breast feathers in the same way.

I tried the GW Teal as a Hornberg and have caught quite a few brookies and panfish on it.

In short - let your imagination run wild. Have fun.

Tim