Mostly where your kids hang out? How about asking your kids for ideas of large art to hang on walls? I wouldn’t do shelves & smaller pics in a space like this.

Get some posters of things that interest your kids. You don't need all that stuff on the wall, it will create a cluttered look, especially those things near the door and floor.

What do your kids want?

I used large framed movie posters that the kids liked. Easily changed out in the future. Other options considered were music- or gaming-related posters.