Continue load-bearing walls for house extension

Greetings!
The idea has been around for years, but until now other projects were more important.
The ground floor plan of our existing house with attic is to be extended upwards (either built up or with a saddle roof). The load-bearing walls should be in the same places.
At the moment it is still just an attic, with an insulated concrete intermediate ceiling accessible via a half-landing staircase with an east balcony overlooking the completely uninsulated roof structure.
The easiest way would probably be if only the roof were re-covered, since the 1m wall enclosure would also offer a pure attic conversion.
But our son, who (initially on his own) wants to live there, is very tall and doesn't like sloping ceilings.
The attached hand sketch is my idea for the new floor and I look forward to numerous feedbacks. As a family, we are open to ALL new ideas.

Why is it that I don't receive a single response?

Why is it that I don't get a single response?

Because the question is not really understandable. Is a building supposed to be added onto + a new attic built on top? Is only the attic supposed to be converted? Plan without measurements. Are roof slopes taken into account? Etc.

I can only make limited sense of the confusing description; I believe I have understood the following: the floor plan represents a combination of the current actual ground floor and the possible use of the upper floor (?); the attic is not developed, but has a knee wall of 1m (?), but the future occupant of the top floor / new upper floor would prefer it without slopes. In other words: a one-and-a-half-story house (or basically a bungalow with a knee wall attic) is to be expanded into a two-family house of the "Stadtvilla" building type.

To make matters worse, one currently couldn't even tell how the roof, that is the ridge direction, is supposed to run. Whereas with 3 balconies, a gable roof with a knee wall actually couldn't fit.