I don't know Halifax too well so I'm armchair commenting, but Rainnie Dr. - the street that's slated to be pedestrianize - looks like it's very peripheral in nature. Based on apperances, it looks like it mostly serves as a slip lane for the occasional eastbound driver who wants to avoid the Cogswell-Gottingen intersection and free on-street parking for people who want to visit nearby things. Losing it doesn't sound like it will affect traffic patterns much.
The street looks really forlorn. The hydro poles obstructing the view of the Citadel are really unfortunate. That proposal - even if we don't have any idea of the architectural details from that massing diagram - will be a huge upgrade in any case.