The points you made are entirely correct. Although, the line already cuts through the Bareilly - Nainital state highway and due to the rare times the gates need to be closed, an overbridge will not be needed. The line can help steer Delhi bound trains from PBE, STP to bypass Bareilly and save around 30 minutes. Can also be used if derailment etc happens at BE like it has been in the past, stopping the traffic.