As Gus outlined already, different parts of the country have different priorities. Atlantic Canada has a disproportionate amount of seats to population, and lots of small provinces. Under any reform they stand to lose influence so how do you reform the system in a way where they don't feel like they will be shut out of the system?

Currently most important measures, including constitutional measures, require 7 out of 10 provinces that represent 50% of the population to pass. The same is likely true for electoral reform, so how do you convince the 4 Atlantic Provinces to not block reform?

Then there is Quebec. Quebec always wants an advantage for Francophone voters since they only represent less the 25% of the Canadian population and often are fighting for over representation in the electoral system. If Quebec wants over representation, then it has to come at the expense somewhere, and Atlantic Canada is already in a good poisiton so you need to now give Quebec more representation, Atlantic Canada less without pissing off the rest of English-Speaking Canada.

Then Alberta often is distrustful of the rest of Eastern Canada, thinking reform is a plot to force them out of power and influence. With the Conservative party not in favour of any new system, and the Conservatives being the champion of Alberta, its hard to see how Alberta can get on board of any system until the Conservatives pick one.

We haven't even touched Ontario, which tends to align closer to Quebec on policy matters to ensure a Quebec-Ontario control over power in Canada being the two largest provinces representing half of the overall population. If you can't get Ontario to agree any reform, they represent under 40% of the overall population and the 7 provinces, and 50% of the population rule to agree on any new system is DOA.

And I haven't even mentioned British Columbia, Manitoba or Saskatchewan or the Territories in this. More or less you need to find a voting system that Ontario and Quebec agree to then you need to either pick Atlantic Canada or the western provinces to agree to it, as I doubt either side will agree with the other. And regardless, you will have unhappy people somewhere in the country.

If this all seems needless complex, then yes, it kind of shows why we can't agree on anything and why reform is DOA.