I know i am terrible at this sort of stuff but here is my idea of what to do with the Bay. It would be modeled off of one of my favorite buildings; the Tip-Top building in Toronto which is now redeveloped into condo's. By the way, i have no idea who would fund such a thing and it would surely be very expensive, but it is just an idea.
I was thinking a similar thing for the bay. Please excuse the low end Paint render. My idea is to (i know, blasphemy - but i am trying to save the building, but....) cut the building in half. Horseshoe each half and build an addition on top - al,la the Tip-Top Building and run a streetcar or LRT line through it, down Graham to Main St.
(....the streetcar would run down Osborne to crazy corner and back up to Main St and connect up to Graham again. But that is for another thread)