On the question of the loonie, I wasn't really suggesting that we adopt it, but rather illustrating my reaction to Cailin's suggestion of the non-circulating gold coin. Quite correct that it would be an in-joke.
With respect to the word graphic, we could make it square by rearranging the letters as
CAN
ADA
So there are lots of possibilities.
If we want a shaped flag, which shape? Tim Horton's?

(I know, another in-joke, and there'd be trademark issues.)
(And does anyone else notice the resemblance of Australia to a dog's head? He's looking to the left, with Tasmania as the tag hanging from his collar.)