Kissing one’s wife’s hand in front of other people in the street

This is one of the things that go against true manliness or chivalry (muruah). It is very cheap and vulgar to do this in front of people, because this is a kind of foreplay with one's wife in front of others. So keep away from doing such things. You can show your love for her in other ways, and when you are alone with her, you can do whatever you like, within reason.

May Allah help us and you to do all that is good.