This is incredible work! The wings look great, and the steel armature looks very precise. How in the world did you machine something so intricate? Truly impressive. I can't wait to see the whole thing together.
I wonder how this might work for something of a much smaller scale and the feathers need painting/detailing?
what I would look into is having artwork printed on the vinyl , that would be my first test.
I was always thinking of having feathers made like how they make faux flowers! some of that stuff is very real looking !
My "original" idea was to make feathers "individually" on bristol paper(a heavy gage/weight) and color them with pastels or ink(whatever yields best results-do a few tests).The paper can be folded and formed as well as hold shapes.I'd probably back it wtih some wire,but it sounds like allot of work.Your idea is probably better and far more efficient.