I think this one and others could be a subject in developers part.
In my imagination I see an entry in Menu like "Tools" or "Generators" with few entries:
-shape generator
-stairs or staircase generator
-roof generator
-furniture builder
-terrain generator
All of this could be made as individual plugins.
First step was made by shape generator.
For stairs generator could be used as start point for plugin developers the code (free) from AOI named Array... in combination with shape generator.