Proto dragonSketches

well, I was thinking about the origins of the wings of my dragons, and It occured to me I had to rethink the idea, or at least modify it. So the two main dragons you see are the two possible ancestrial creatures. One is the flying lizard. Their ribs couldve modified into handlike wings by the mid jurassic. Makes sense?? The other would be a primitive quadraped relative of the common ancestors of crocs, pterosaurs, and dinosaurs who evolved modified ribs in the early triassic or mid triassic. The one on the upper right, is the how wings would evolve on biped dragons.

Basically, I want opinions from people on which seems a more reasonable explanation for the wings.

Oh and anyone who is good at skeletals, feel free to make an accurate reconstruction of the evolution of the modified ribs over time. Similar to the cheap attempt I have on the bottom.