I'm a fan of tower developments, but just to a certain extent. As pman said, it looks like a really nice Victorian building and while we IMO still have enough Victorian houses in Toronto, this one seems very solid to me. Either leave it be or remove it completely, as rro pointed out.
For the rendering:
The brick sidewalk is terrible, It sort of makes me dizzy, in the wrong kind of way. I would definitely keep the trees and maybe add some more, instead of the seating. In this context, the tower doesn't go very well with the remainder of the original structure. I would rather see a complete glass tower, maybe wrapping the original Victorian facade into glass...