I don't have an opinion on the ending line (I'd forgotten what it was), but I'm actually glad Morn didn't get the "last word".
It was probably tempting to have him eventually startle the audience by saying something strange/profound/etc., but I like how the producers had the "integrity" to not give in and have him speak. Ever.
I don't recall much of WYLB, but I hope Morn inserted somewhere in the montage. I'd hope more than once, too, and kind of hidden in the background as a little joke during what were supposed to be emotional/sentimental scenes. eg, we see a bittersweet memory, and there's Morn in the background.