Love the look of the lower jaw and how the teeth are set into it. The smaller details like the swirls on the joints of the wing, the wrinkled wing edges, making them look more weathered, more worn, the swirls on the joints making it seem very different, very unique, almost toy-like, but also very mythological at the same time. I like how subtle the muscles of the wind shoulders are, it's not just lean muscle making this beasty up. The red pupil and edge of the mouth-webby thing (what would you even call that? lol) Absolutely love.
I also like how twisted almost the forelegs are in positing, but the dragon is perfectly balanced. Done precisely perfect so that it works, but certainly makes it look odd, but totally cool.