Most of the Canadian artists I'm familiar with don't play up their national heritage. I don't know either of these two (though I have heard of Chilliwack) so these are first impressions. Overall I agree with your differential.

A longer song should (with exceptions) be complex enough to merit the extended length, and a short song should be essential enough to merit the brevity. I think both succeed in this endeavor. Though I like the brisk guitar solo on Wanna Rock, there are other brief songs I prefer (shoutout for the Rubinoos).

My Girl: 88

Wanna Rock: 85