So my house was built in the 70's and has a lot of different odd levels, such as the kitchen which is a separate slab higher than the rest of the main floor. I took out the railing as you can see in the pictures (bc I hated it) but now need to put something in to differentiate the space for safety reasons. I am thinking of adding a step down into the living room like the one on the side to keep the space open or at least a partial step but m looking for other option. I know the step is a necessity, but should I add a small bookshelf or something else so that no one backs there chair off the ledge? The first picture is just to show the old rail and height of the ledge. The second picture is what I have done so far. Please help.

Ignore the floor damage in the last picture it has since been fixed.