160 sqm single-family house without basement - 2 full floors with gable roof

In the meantime, there have been some changes to the property (survey, slight adjustment to the BP) and the as well. I assumed that the old thread wouldn’t be helpful...

Actually, it is, because you can quickly look through the dead ends that were previously tried (and that may have been commented on to you at the time). The majority of helpful people in forums are not afflicted with my forgetfulness defect, but no longer have that in short-term memory after a six-week break.
If such hints are omitted, a likely consequence is advice that has already been reasonably rejected before, which is then unnecessarily repeated. Compared to people who "sacrifice" their coffee break for that, it’s not nice (and incidentally inefficient for oneself as well).

... and, new ground floor layouts with modified stairs as in are unfortunately also ineffective if the upper floor is not adjusted.

I don't like the whole development history: not only the attempts shown in the old thread but also the architect's memorized sketch, which "resemble" a single basic design that is only gently stirred up. In this respect, I have the impression, a) that your thoughts are going around in circles too much, and b) that the architect was probably just a general contractor draftsman who stuck to the client’s proposal accordingly.

Therefore, I suggest the following therapy: start on a blank sheet instead of just "improving" previous versions, and: instead of copying, find a creative (= free) architect.

Next to the staircase, there is a long useless corridor to the WC, without being able to properly fit a cloakroom there; without a basement, maybe the pantry could be more cleverly placed under the stairs?; the technical room seems arbitrarily sized to me, i.e., without a concrete concept of what should be where; the separated living room seems more like a TV room to me; the bathroom (and probably also the bedroom) only works under the condition of a fully right-angled upper floor; I never see the air space giving the house back the generosity that was forgotten in all other corners.

My conclusion: although the drawings themselves appear more mature than the amateur attempts of some others (especially with the same "planning software") here, I would see their implementation resulting in the typical clumsy general contractor’s villa caricature.

: The problem is somewhat the size of the landing staircase.

A landing staircase needs its space. I don’t see any landing staircase in this hallway. It simply doesn't fit.

I never see the air space giving back the generosity to the house that was forgotten in all the other corners.

Even though I find @11ant’s words and sentences partially just as clumsy as the mentioned amateur attempts of some others, I have to agree with him about the air space.

Even though I find @11ants' words and sentences partially as clumsy as the aforementioned amateur attempts of some others,

What I meant to say is: here we see – especially with some planning software tinkering – all kinds of clusters of rooms, which themselves are clusters of wrongly dimensioned furniture symbols and passage dimensions; not infrequently combined with air spaces / galleries etc. that have been adopted 1:1 from show homes of different size, naively underestimating that the sense of space cannot be scaled down arbitrarily. What the OP has patched together in this respect at least does not have as bad a Tetris factor as other such works. But I would – if it were actually built as shown – "see" some tears of disappointment shed because it looks quite different than expected. Therefore my advice: reengineering instead of tuning, and let a professional take over.

The smallest house known to me with a visually well-functioning air space is, by the way, the "Streif Haus Musterhaus Köln" (~10m x 8.5m). Since the house exists as a show house in reality, there are also numerous photos of it that convey a very pleasant impression. So, it can also work well in a small space.