Today the ten MLAs from Yorkton-Melfort-Humboldt are all from the Saskatchewan Party. Although 27% of those voters voted NDP, they elected no representatives. Conversely, only three of Regina's 11 MLAs are in the government caucus, although 37% of Regina voters voted SP.
With a regional open-list Mixed Member Proportional (MMP) system such as the Law Commission of Canada recommended (but with smaller regions), if Saskatchewan voters voted as they did in 2007 they would have elected 30 Saskatchewan Party MLAs, 22 New Democrats, and six Liberals.
See MMP Made Easy.
That's using a model with at least one-third of the MLAs elected regionally, in five regions. Three local ridings would generally become two larger ones. You might have 37 local MLAs and 21 elected regionally.
One interesting difference would be the 12 MLAs from Moose Jaw-Swift Current-Estevan-Kindersley: instead of a SP near-sweep, my spreadsheet projects three New Democrats and a Liberal, once NDP votes and Liberal votes count equally with SP voters. That would include the two regional NDP candidates and one regional Liberal candidate who got the most votes across the region. Maybe NDP voters would have elected Glenn Hagel and Sharon Elliott or Ken Crush, and Liberal voters Colleen Christopherson-Cote or Tim Seipp or Michael Klein. The 12 MLAs in that region would be eight local, four regional. The SP would no doubt have won seven of the eight local seats, so those SP voters would even elect one of the regional MLAs.
Another change would be the 10 MLAs I mentioned from Yorkton-Melfort-Humboldt: instead of an SP sweep, we'd see three New Democrats and a Liberal. That would be the three regional NDP candidates who got the most votes across the region (maybe Randy Goulden, Marlys Knezacek and Jordon Hillier) and the top-voted Liberal (perhaps Brent Loehr). The 10 MLAs in that region would be six local, four regional. Those SP voters would no doubt have elected all six local MLAs.
Of course, this projection simplistically assume voters would have cast the same ballots they did in 2007. The reality would be different. When every vote counts, we typically see around 8% higher turnout.
And we would see different candidates. Note that, when the SP members from Moose Jaw-Swift Current-Estevan-Kindersley met in a regional nominating convention, they would have not only voted to put the eight local nominees on the regional ballot, but would have added several regional candidates. With only one or two women from the eight local ridings, when they nominated several additional regional candidates, they would have naturally wanted to nominate a diverse group: more women. And 90% of Canadian voters say that, if parties would nominate more women, they'd vote for them.
Conversely, SP voters across Saskatchewan would also count equally. In the 12 ridings of Regina plus Indian Head - Milestone, instead of four SP MLAs we'd see five, and a Liberal (maybe Michael Huber.) If the SP had won three of the eight larger local ridings, who would Regina voters have chosen as the two regional SP MLAs?
The 13 ridings of Saskatoon plus Martensville were less skewed. Instead of seven NDP and six SP we'd see five NDP, six SP and two Liberals: perhaps David Karwacki and Zeba Ahmad?
The 11 ridings of Prince Albert - Battlefords & North would have an extra NDP MLA (perhaps Maynard Sonntag) and a Liberal (perhaps Ryan Bater).
The exact numbers might be different if Sakatchewan had four regions rather than five. But this is only an exercise in projection: the real results would have been different when more voters turned out to vote in what are now "safe seats."
As noted in previous posts, I prefer regional "top-up" MLAs elected personally under the "open list" model. You would have two votes, and more choice. "Open list" means that voters can vote for whoever they like out of the regional candidates nominated by the party's regional nomination process. The party would win enough regional "top-up" seats to compensate for the disproportional local results we know all too well. Those regional seats would be filled by the party's regional candidates who got the highest vote on the regional ballot. Canadian voters have twice rejected models with closed province-wide lists. The open-regional-list mixed-member model is used in the German province of Bavaria, and was recommended by Canada's Law Commission and by Scotland's Arbuthnott Commission.