A 2nd E-W heavy rail line needs to happen within the inner and outer downtown core after the OL is constructed, specifically for the area west of University. If the OL's priority is connectivity and more express-type service between the local and regional (GO) network, then a theoretical rapid transit line would serve as a more localized service alternative. Ultimately, a future rapid transit connection to the Liberty Village Station is also a must. One way to achieve that connection is a King line through downtown and up Dufferin St as others have proposed. A westward OL extension should then move along the railway corridor and hit desperately needed transit nodes in Parkdale and Humber Bay, which allows for connectivity with the proposed Park Lawn GO station.
An easterly extension of the King line would ideally cross the Don River/DVP and traverse Queen, linking with OL at Riverside and moving east towards the Beaches, likely terminating at Woodbine. A branch into the Portland's would be achieved with a proper streetcar connection with Cherry streetcar at Sumach. The key factors favouring a Dufferin St rapid transit line is the massive redevelopment potential along that street but also massive redevelopments either occurring or in development at Dufferin Mall (Bloor), the Galleria (Dupont) as well as E-W development along Dupont, and at St. Clair between Stockyards and Dufferin.