I once wondered about this same thing, people complimenting my smile but not my eyes, nose, other features. then I took a psychology and criminal justice course. people complimenting eyes can very easily be misinterpreted as a sexual thing. when two people are dating or "into" eachother they make a great amount of eye contact. stare into each others eyes, so te first thing out of their mouths is "I like your eyes" but if you have someone who rarely makes eye contact thats a suspicious thing in the criminal justice system. people look to the side a certain way when they are lying.

so complimenting eyes on someone can be quite controversial, a person may take it as someone sexualizing them or calling them a liar.

straight on eye contact in a social situation is a rare thing.

when I asked my wife what part of me is her favorite physical feature on me,.. that depends upon her mood and where her thoughts are. but on rare occasions has included my eyes. mostly she notices my smile because my whole face changes with my smile. but with eyes theres not much showing emotion they can do. either they look up, down to the right or to the left. the eyeball isnt meant to be a physical attribute / attached to emotions. but a smile that says someone is happy, enjoying the moment and who they are with and the conversation. a real and honest smile conveys so much more than an eye ball color and whether it moves up, down right or left.

I personally think my wife is right on with this. I rarely make full on eye contact for more than a few seconds, when in conversations outside my job, Im usually looking this way and that, hypervigilent - where are my children, what are they doing, whats going on around me, is there any danger present... does everyone have their masks on right....bla bla bla, my mind is constantly multi tasking so of course my eyes are not solely focused on the other persons eyes. I do notice though when a persons voice and smile shows happiness, excitement, or sadness and other emotions.