first of all, what about kana saying he’s average?? did mc just ignore that?? second of ...

I don't think it was kana that said naho was average idk it was confusing for me (⊙…⊙ )

From what I believe, he said Naho is avarage to "ward of potential competitors"

loll i was confused readinf this soo

So you don't understand boys so much. Usually when a boy is eyeing a girl, he will tell his friends that she isn't good looking/is boring and etc so his friends don't look at her, thus making less competition.