[balletomane]

Answering my own questions above,
Our cultural scene would be like that of today, except our world-class institutions like the WSO and RWB would be more internationally recognized and far-reaching. The Exchange District would be the location of the theatre scene, much like today, except there would be world-class schools like Julliard located there. Some of the older warehouses immediately off of North Main would have been demolished, making way for some historic high-rises, perhaps reaching about 30 stories. It would be the same with Portage Ave., historic skyscrapers lining the street up until about the location of the former Eaton's store.
Aboriginal culture would still be very important in the city, but the proportion of First Nations people would be less, since the city would be much larger.
Winnipeg would have a WHL team, as well as MLB.

We would still have a diversified economy, except manufacturing would've become much more dominant. The St. Boniface area, would have attracted other major meat packing plants, more than just Swift and Canada Packers. The aerospace industry would've looked to Winnipeg to have their national and international headquarters, because of our central location.

Winnipeg's highly urbanized area would reach mainly along the rivers, reaching northward until about Selkirk, westward including all of Headingley, southward to Ste. Agathe. The east side would've been the location of the industrial parks, so the residential areas wouldn't extend much past the Perimeter, all though industry would be built out closer to Dugald.
Oakbank, Lorette, Niverville and other nearby communities would all be much larger and would be home mainly upper class families.

The entire South Portage neighborhood would function as the Financial District, like Bay Street or Yonge Street in Toronto. Memorial Blvd. would be filled with beautiful limestone buildings on both sides, about 5 to 10 stories in height, framing the Legislature.

The north end would still be the most disadvantaged part of the city, River Heights still one of the wealthiest. St. Boniface would still be a separate city, perhaps amalgamating with St. Vital and Transcona only, with a population closer to 250,000. Although the percentage of French-speaking people would be less, St. Boniface would've bolstered about being one of the largest French-speaking cities in North America.

Crime rates overall would be lower, but still centralized in the areas north of Downtown. The concentration of crime in these areas would make them even more so than today an "area to be avoided by tourists".

Brandon and Portage la Prairie would have populations closer to 100,000. Other nearby cities closer to 50,000. A larger Winnipeg would've capitalized more than it did on the north, with The Pas and Churchill being hubs of the north, with populations around 50,000. Imagine The Pas like Prince Albert and Churchill like Thunder Bay. However, both of these cities would be in decline since the 1960's, with high crime rates and blighted areas.

Winnipeg would still be "Chicago of the North", and maybe Chicago "Winnipeg of the South".