It's just the flight timings are pretty awful. No late afternoon / early evening service at all between YMM and YVR. There's also no proper late-night service between YVR and YMM.

And the morning service on AC/QK between YVR and YMM is kinda harsh with the connection. A 6:00 a.m. departure only to arrive a little after 11:00 a.m. This will make my commuting idea a little more impractcal. :-)