The original proposal was really nice, some version of it would be good to see - I'd imagine that even if the Grosvenor plans change completely, a couple towers plus retail at a high density urban treatment is likely. Combined the site is large enough for something really serious in scale and intensity here, far beyond what the area has currently. The block itself will fit a ton of density, but it also is fairly close to ground-zero for a far more urban future of Calgary. As impressive as the city centre has been growing the past few decades, the walkable retail catchment population 30 years from now on this site will be absolutely massive and dwarf today's numbers.
What would be pretty cool is a pedestrian-oriented retail wrap, combined with a movie theatre above + some towers. It's a staple of Canadian "big city" design - Vancouver, Montreal and Toronto already have multiple of these. It's our turn and would complement the urban format box store cluster over at 8th Street & 17th Ave as another serious anchor of retail activity.
Hopefully we don't get a dirt patch or parking lot for too long.