Wow, all of these are really well done. Nice pov/comp on the exterior shot. You did really well capturing detail in the tough lighting conditions of the hall shot. The piano shot is killer, as others have said (although I agree that I would have liked to see all of the stool legs), the angle at which you took the suit-of-armour shot rawks, and the light/shadows on the organ shot are lovely.
(The gardens are free on Tuesdays, so although I visited them last year, I still haven't been inside Casa Loma since the public school trips either!)