I am going to agree that there is lots of land available for re-development in Toronto.  I see strip malls that could be redeveloped into nice homes if we put mid-rise buildings on a human scale there.  Put the small stores on the ground floor, and you have  a nice mixed use building.   Think of Paris or Washington scale buildings, not the glass boxes in the sky being built now.  Make the units large enough for a family.  Build subways to Scarborough and North York where these strip malls exist to provide transit.   I also wonder how the infrastructure in the mega-developments like Liberty Village will hold up.  All those toilets in the sky...