Some urban planners believe that every light rail line must stop every 400 m. No problem delaying 200 riders already on the train, in order to serve 5 riders at a minor stop because those 5 can't be asked to use a parallel local bus.
And then, another group of urban planners thinks that GO RER connection to the major Lawrence East bus route isn't desirable. It might cause a few riders from upstream to stop taking transit. So much for the network connectivity.
Btw, the Uxbridge Sub corridor is relatively wide around the Lawrence East station. If there is no need to reserve space for 2 LRT tracks or 2 subway tracks, then it should be possible to have 4 mainline tracks there. One pair for trains that stop at Lawrence East, another pair for passing trains.