Very briefly, I think it would not be fair. I think if there is going to be a proportional component, Yukon should be part of it. It will take some detailed changes throughout the contest, but the spirit of the principle should be the same. For example, I disagree with some of the comments that I heard here. Let's say a proportionally elected list candidate: there could be one list candidate for three northern territories, and that would perhaps result in a slight increase of numbers of MPs, but only slightly. It would not create chaos. And no, this candidate is not a problem, because he's not purely representing Yukon, Nunavut, or NWT.
I can give one very powerful example, because I spent half my life in a first-past-the-post mixed proportional system. One of the most excellent projects on a global scale in the last 25 years came from a list candidate from the Social Democratic Party in Germany. Hermann Scheer initiated the renewable energy source legislation, passed in 1999, which became the model for renewable energy in China, Denmark, and many countries. This was widely accepted.
Excellent people who come in as a list candidate are looked at and judged by different agendas and represent communities very well with somewhat different aspects from the first-past-the-post candidate from Yukon, Nunavut, and the Northwest Territories. They're just throwing this out wisely; we may have one proportional representation counted out for these territories. From half of my life experience, this could work very well.