All flights from Europe to the US are dayflights. However, to the West Coast, there is also the option via Asia that there are overnight flights. The flights will be slightly longer and I suspect may be more expensive.

There is also KL681 from AMS to YVR leaving at 3:35pm arriving at 5:30pm.

DL makes you change in Salt Lake City which means you have to clear US immigration and customs with 1 hour 5 mins connection. I would personally never do this.

I would go with the FRA or AMS connection for ease of you remain within the same terminal building but have to cross from the Schengan to non Schengen parts of the airport. The AC option via LHR means you have to get from T2 to T3 and LHR is prone to delays like JFK.

There is also a 10:05am CDG to Montreal via Air Transat connecting to Air Canada which gets into YVR at 4:35pm so same timings as the Delta flight. Cannot comment how good Air Transat is or if 1 hour 10 mins is suffcient to clear immigration and customs at Montreal. A bit tight.