Various factors play into the overall value of a coin, with all things being equal the Perth Swan is far more pleasing than Perth's Wedge eagle or the Emu, the subjective element.
Bird coin collector's like @punkysdad would even love to have the Emu in his Stack.
Come on PD, get off the sidelines, I'll help you make your first post, Okay?
I wonder what Captain Cook's reaction when he came across the Emu?

Always, with Love 🤗 🌺 💖