As one of my colleagues pointed out, one of the big questions around the model you are proposing has to do with the size of the regions where this form of proportionality would apply. You gave the example of the large Ottawa region, which would have six ridings. Those ridings would be reduced to three, and three other members would be chosen to represent the region. The number six is a model. Then, you talked about Toronto, which would be split in two. I'm not very familiar with Toronto, but I believe we are talking about 20 or so members in each of the regions. That way, a candidate who obtained 5% of the votes could be elected.
The rest of Canada has many rural regions, so there wouldn't be a standard model where each region had six members. I'd like to hear you comment on that.