Assuming the land in that spot isn’t horribly contaminated by PCBs as one person familiar with the area told me 3 years ago, I’d like to see mixed housing, a grocery store, and a pedestrian/cyclist bridge or tunnel into Downtown constructed. If it is contaminated, then it might only be useful for a pedestrian bridge where no one will tend to spend much time. Or if it needs longer term use by residents and businesses, then decontamination is available in Montreal by rail for a billion or more dollars. Why was the City in a hurry to buy the land once it was known the Stadium II wasn’t going there?
Since a train station will one day need to serve Downtown Regina, a suitable space north or south of the tracks should be set aside for that purpose.
Also, a space for a school would be a good idea, to make Downtown more of a ‘complete community’.