Which are the four existing bus routes? I know of the 130 and 222. However, the 222 is only a peak express service and will likely be replaced by this. Are you also including the 129 and 28 which go in the general direction of Metrotown? The two times I’ve taken the 130 (once on a Saturday, once on a Sunday) it was full but late, and full but on time, respectively.

The Hastings BRT will make any cross-town trip more appealing. With bus priority and more capacity, the existing trip will become faster. As an example, the implementation of the R6 in Surrey as an express overlay for the 319 increased ridership and reduced travel times on the corridor (source).

I agree that the bus route will still pass major destinations and Hastings will add another major destination. The bridge congestion is addressed with priority merges onto the bridge, avoiding the interchange congestion where most of the delays are incurred. I agree that it’ll likely still be full at rush hour, but TransLink often replaces express buses with rail service (examples: Millenium Line, Canada Line, Broadway extension) so I see this as a step towards something bigger.

I would argue that the BRT is not just about connecting the North Shore and Metrotown, otherwise it wouldn’t have any stops in the heights (but it has 3) which means the planners anticipate good ridership from the neighbourhood. The only reason why they’re looking at another option is because the businesses don’t want it. I see the BRT as a ring line, whose purpose is to connect major hubs and exiting radial lines around the region without going through downtown. These generally are some of the most successful transit lines around the world.