I have small feet for a guy. When I shop for shoes, I usually need either US size 7 or 7 1/2. Usually, it's 7 1/2, but New Balance seems to run big, so I need a 7 from them typically.
As for how men's feet look as opposed to women's feet, I usually don't pay much attention to men's feet. However, if I know a guy is a real jerk and/or is a man with power (POTUS, leader of another country, politician of almost any kind, major CEO, etc.) it is weird for me to see him barefoot or in sandals. Due to my tickle fetish, being barefoot, to me, means being vulnerable to having your feet tickled. If a man--or woman, honestly--is a jerk or has power, it is strange for me to think of them being tickled. In fact, sometimes I almost do not want to think about it.