If your wall is empty, I see them as an opportunity for creativity.
I do not know your personality, so I’ll give you some ideas for some personalities.
shelves displaying trophies are fun,
like a shadow box with your medal.
Framed achievement certificates,
One of your paintings or drawings
ceramic bowls, and artwork
wire design or monogram
collage of fashion magazines
Another good thing is the fishbowl stuck to the wall.
But before that make sure you have one electrical outlet on each wall. If not, you need to install it on a wall that does not exist. But make sure everything is white.
You can also paint a wall and then have a graffiti (if that’s your style)
or choose a theme for the wall (eg.sunset) and leave it painted.
It would be even better if you could position the sticky board with a body painted in purple, blue and lime green. On this sticky board, you can handle images or position them randomly. You can change it from time to time, if you want a new look every time.