How big of a sofa/loveseat would I need to get to comfortably fit 2 people? 3 people? I've tried several sofas in-store but it is hard to visualize without the other person being there.

Looking at several different sizes - loveseats on the smaller side (seat size 45" x 22") -> would this be able to comfortably seat 2 people without it being awkward? Or would I have to go up to a sofa size (seat size: 64" x 23")?

Have been reading some articles about selecting a sofa but none of them really give any guidelines in terms of size.