Actually in seminary we had classes about loshon hora in connection to shidduchim and were given phamlets about it to give to our parents. My mom has gone to some speeches on the same topic.
Back to the topic at hand, I think it’s stupid to ask if someone is good looking or not. Ask for a description. No one is going to say “Yeah he’s really bad looking” and I think the majority of the world fall into a grey area, not terribly drop dead gorgeous but not horribly ugly either.