Housing addition for interior

I am here doing decorating and it just hit me. In all size houses we have the ability to change floor, wall and chandelier. Why do we not have ability to change stairs?

I'm here trying to do a modern build and it occurred to me that I can't change the look of the stairs or banisters to match. I really would love to see this implemented as it would help alot of people with their build concepts

I couldn't find where to edit. I would also like to add in a new style of partition. I love them but you use one at beside the stairs in a medium and it pokes up. So what about a shaper tool or partition that isn't fill. It has an angle cut to fit under those stairs perfectly.

To allow for easier walling in of that area if you wanna