Sometimes, unfortunately, the US citizen line seems just as long as the regular one.

If it is just the YXE flight coming in, then immigration will be a breeze, but sometimes the timing works against a person, alas. Last time through about 10 days ago, I must have passed about 60 + people--they were on the moving walkway and I wasn't so you know I was really moving it (though not quite running!). One tip is to stay to the left on the overpass (it goes over a taxiway/ramp) as the steps down to immigration are on the left for non-US citizens. The moving sidewalk is on the right and people often are confused when they get off there as to where they should go. If time is tight, it is an opportunity to pass people without being rude.

I'd head into Saskatoon to pass the time, likely to Broadway, if I were you, as others suggest.