what sorts of things do mature adults hang on their walls?

Completely non-controversial and inoffensive wall decorations are what you find in a waiting room at the dentist.

I look at people’s walls a lot when I visit a house for the first time and if it’s nothing but landscapes and a few pictures of loved ones, I just think they must be the most bland, boring people on the planet. I want to see somebody’s personality when I see how they’ve decorated.

My wife and I compromised. The stuff that shows we are mature and adult is downstairs, and my stuff is upstairs.

Regards,
Shodan