The eastern stretch of R-L from Robert-Bourassa to St-André is not terrible because it has street trees and a planted median. It's a bit like one of those anonymous arterial boulevards you find just outside the historic centre of most European cities:
The central stretch is the real problem. The sidewalks are narrow, there are virtually no trees, the highway-style lampposts are unspeakably ugly. This should be the teeming heart of the city but it feels exactly like somebody tried to wedge a suburban arterial through the middle of downtown.