There are some interesting re-routing of the line assignments if the Evergreen Line ever gets off the ground and running. It looks like the original plan that was done many, many years ago when the Millennium Line was first planned and the Port Moody-Coquitlam (PMC) Line was supposed to follow closely.
Trains running from Coquitlam Centre would likely have more passengers than trains from Columbia, Sapperton, and Braid. It seems to make sense to me. So they should have the more direct route. However, that little portion between Lougheed and Columbia is going to seem like a waste of money if it only plays the minor role of a connector shuttle.
Perhaps some of the Coquitlam trains could run from Coquitlam Centre to Columbia. Of course, that all depends on how they end up configuring the tracks at Lougheed Town Centre. The station is already pre-built the ability to accommodate a third track on the north side of the station (see photos at Just a Gwai Lo)
It’s nice to dream and all, but we will not have an Evergreen Line if there is no money to run our buses. So until we see the shovel hit the ground, don’t hold your breath.