In your top three...and due to be bulldozed if the latest Calgary Zoo Master Plan remains on course. The plan is for the Prehistoric Park area (the sprawling dinosaur zone that you skipped) to be demolished in favour of a brand-new Amur Tiger/Takin/Japanese Macaque area. Possibly a Tropical House as well. The current tiger enclosure, which is basically a big Howletts-type cage and one that I like, would be gone and replaced by a building.
@ZooElephantsMan I put it just behind Minnesota Zoo and the Alaska Zoo for Amur Tigers. Other standouts on my trip have been Henry Doorly Zoo…with Zoo Montana and Pittsburgh being a bit further back.