Make signs from the "Intersection" Mask, preventing them from spawning too close to top or bottom

Make corner meshes from the "Upper" Mask, preventing them from spawning in the lower area

PS: corner points subgraph modified from the wall subgraph

Ladders are all at the above and signs are not exceeding the building heights!

Adding Doorways

Placing every door could be troublesome so we'd spawn some doors automatically with a single number

To make it clear, we need to randomly pick one or more points on the 1st floor and turn them into doors

Here's the subgraph for the bottom part, while the key part will be the blueprint

We first get the input context ( which will be points) and keep everything like tags set so that they won't be missing after we've done the math

Count the points and shuffle them using the Random Stream node, then pick as many as we wanted

Set every point's density in the original point array to 0, set the chosen ones' density to 1, and construct the point data with points and other stuff

Don't forget to add the return node at the first loop!

We can now pick some random points besides our buildings and spawn some doors!

and it fits well with the city and other meshes!