When you have shot one bird flying you have shot all birds flying. They are all different and they fly in different ways but the sensation is the same and the last one is as good as the first.
Archaeopteryx probably cannot tell us much about the early origins of feathers and flight in true protobirds because Archaeopteryx was, in the modern sense, a bird.
On the contrary, there is a considerable body of evidence that these fossil traces, known as 'dino-fuzz', have nothing to do with bird feathers... I, and many others, do not find any credible evidence that those structures represent protofeathers.