saskriders
Can't Hold Leads
Well, for one - coming from some ridings with effective MPs I would not want to see ridings significantly increased.
You'd also end up then likely concentrating the power even moreso in the hands on Ontario and Quebec.
And I'm saying that if you have a multi-winner (so I'm assuming we're just doing 2 per riding)... you're either going to have NDP/PC, or PC/Liberal, and maybe in some rare instances Liberal/NDP.
Because even with an STV system, all the little guys are still going to get dropped out to add their votes to the big guys eventually.
Regarding your criterion listed... STV fails Condorcet, Participation, Monotonicity at the very least, and I believe that it could fail Reversal as well.
There's no perfect preference system so introduce IRV first, as a stepping stone. This way you start seeing more votes for other parties such as Green, and it's possible they may get enough votes in some ridings to win as a result since people are confident enough to put them as a #1 choice (and if they don't win, at least your second choice of big party can apply).
From there, over time perhaps other methods can be built on that base.
But I think we can agree almost any preference system is better than FPTP.
What is wrong with increasing the size of the ridings? There would still be the same number of constituents per MP, and bigger ridings doesn't mean MPs would be worse. I would actually argue they would be better, because even in regions dominated by one party (where bad MPs, for example Rob Anders, get elected) they may win only 2 of the 3 seats in a riding with the big party's least competent candidate losing out to another party's most competent.
Power wouldn't be more concentrated in Ontario or Quebec. The seats per province wold stay the same.
I don't understand what you are trying to say in this paragraph. Who cares if the Conservatives, Liberals, and NDP get most of the seats, they get most of the votes. PR and STV aim to make the share of seats reflect the share of votes, not kick out the big parties. And smaller parties would still get a few candidates in if they were popular enough in a riding. For instance, assuming the vast majority of ridings return 3 candidates two might go to the big parties. But the final seat may go to the Greens if people who voted for eliminated candidates listed them as an alternate choice. Keep in mind that the Greens won a seat, had a second place finish, and had 17 third place finishes. Irregardless people who want to vote Green can without splitting the vote.
I don't think STV fails Condorcet. Do you have any mathematical proof? I can show some for all the things I listed for IRV if you would like.
STV only fails participation criterion if a voter ranks candidates he doesn't like. If for instance I ranked NDP, Liberal, and Green candidates only I would never be helping the Conservative candidates. I believe monotonicity would be the same, but I am not 100% sure.
I agree IRV is better than FPTP, but I still think it is a bad system. Ideally we wouldn't need a stepping stone, and could go immediately to PR. Many countries already have adopted some form of PR. Canada is behind the times.