The advice to not count on the NB Starlight is sound. As pointed out, it's not nearly as bad as in the past, but there's a good reason it has been nicknamed the "Starlate".
I personally find the Cascades trains more comfortable, as well, but wouldn't consider not riding in Business Class. My experience -- luck of the draw, of course -- is that if I'm in regular coach, there has always (no exaggeration) been a crowd of students, either high school or college, who either never learned or had forgotten the concept of an "indoor voice." At least the CS has one attendant per car to help keep order; on the Cascades, it's more like a British train, where there is one attendant and he or she completely disappears after collecting tickets.