This is more of what you'd expect from a personified oomukade, like that kenkou-cross one.
But Touhou isn't really about monster girls, unless if you count Wakasagihime. Generally animal ears / tail / wings are the max a girl can have, with more monstrous features sometimes represented by clothes. Like Yamame's outfit buttons standing for extra spider eyes, the oarfish fin on Iku's shawl, tiger prints on Shou's dress, etc.