But why can't the system be radically simplified?
Well, looking at your proposal, it is more complicated than Single Transferable Vote (STV) and Party List, as it includes both. And it is an exceptionally complicated party list, as it is a list of representatives per district. So I would say that one reason why proposals aren't radically simpler is that people are choosing hard to implement requirements.
Finally, the top ranking candidates are selected from each district in proportion with the nationwide result. E.g. if 99% of voters voted for candidate A from party B in district C and party B received at least one seat in the nationwide vote, then candidate A is elected. If party B has more than one seat, the next candidate is selected based on the electoral outcome in their district.
But consider what this means. Districts that are overwhelmingly one party will tend to get most of the representatives. Moderate districts where either party could win generally won't, as they'll get beat out by members of their own party from more lopsided districts.
Another problem is that some districts may get multiple representatives. I'll use United States parties, as I'm more familiar with them than with the various Canadian parties. There may be a district where three candidates are competing: a Democrat; a Green; and a Libertarian. There is no Republican, as it's not that kind of district. A Republican would never get enough votes to make it. By percentage, the voting breakdown is
Because the Greens and Libertarians are spread out across the country, this might be the vote leaders for each minor party. So all three candidates make it into the legislature. Meanwhile, another district votes
This district gets no representation. The Democrats and Republicans filled up many of their slots with people who won 80% and 70% of the vote in their districts. There's no room left when they get down to 45%. Meanwhile, the Libertarians and Greens only won a few seats nationally, so they filled up their slots with people who won 20% and 10%. There's none left at 5%.
There are fixes for this. For example, you could limit each district to one representative. But then you'd have the case where the less popular candidate is selected. This is why many prefer "top up" systems like the three proposals in the article. In a top-up system, they elect district representatives and then add representatives to make the system proportional.
Why not just do STV? Then each voter could balance whether they want to vote for the candidate who is best, local, an ideological match, or whatever. The system will combine those preferences among multiple voters. The answer seems to be that they feel that voters need to be limited to districts to get local representation. But my point is that STV is simple to understand (rank candidates from best to worst), proportional, and can work with an arbitrary number of districts. STV also allows voters who want to prefer local candidates to more distant candidates to put those candidates first.
STV also avoids the situation where a candidate gets 30% of the vote in one district and beats out another candidate who would get 25% of the vote in five districts. Because in your system, only the vote in one district counts for an individual. STV selects the best candidates on a more regional (or even national) basis.
Your proposal is also vulnerable to low vote districts. Because you go by percentages, candidates may prefer to compete in districts where only a small number of voters are needed to get a good percentage. And if you change it to votes, you exacerbate the earlier problem where some districts elect more representatives than other districts.
This is not to say that the other proposals are especially good either. But I'm not convinced that your proposal will be simpler in application. It has several flaws that would need patched to be fair, but the patches are likely to make the system even more complicated. And of course it is more complicated than either STV or party list, because it uses both.
The three systems from the article, at a similar level of definition as your proposal.
- Urban areas vote by STV.
- Rural areas vote by first-past-the-post/plurality (FPTP).
- Top-up seats added to make the overall result proportional.
Three steps; one less than yours.
Dual Member Proportionality
- Everyone votes for a party ticket of two candidates.
- The party with the most votes wins one seat.
- Calculate top-up seats from the second and losing first candidates.
Your system may be simpler than this, as the top-up method is quite complicated. Of course, most voters will just vote for their desired candidate/party.
Mixed Member Proportional
- Regular FPTP.
- Add top-up seats to make the results proportional.
Considerably simpler than your system. There's only one party list, and voters don't have to vote based on it. Voters get either their candidate of choice or their party of choice except in a few cases where both are unpopular.