After looking at the draft again, which still appeals to us, but the mentioned disadvantages do outweigh it, or maybe we are still looking for a solution with the bathroom and bedrooms on one level, we have worked on 2 alternatives ourselves.
The external dimensions are fixed, so based on the architect’s drawing, we started to think it through ourselves with pen and paper, similar to how always does so well. If we like any of those proposals, we would discuss them again with the architect and ask him to "make something out of it, as a professional."
On the ground floor, we now have all the bedrooms with the bathroom. Thus, the north entrance is downgraded to an absolute side entrance, and guests coming from the north, including Santa Claus, have to go down the stairs or via the fireplace. We are currently assuming French balconies and floor-to-ceiling windows on the south side for the plan.
For the basement, I have attached 2 variants, as we are still skeptical whether the approx. 9m to the back towards the north in the living room will be bright enough; therefore, we have one variant with the living room reaching the north wall. The 2nd variant then has a technology room behind it. This naturally reduces the space in the dining/living area, but that should be sufficient with 180sqm.
For the basement windows for the living area, there are solutions that do not look like typical basement light wells and are as large as possible. Unfortunately, a light well is not an option because the slope continues upward towards the north, and we could have problems with heavy rain?
We tried to keep the fireplace centered; the architect’s proposal pleased us even though we had not wished for or discussed it that way. But here too, I could well imagine an interior wall as a solution.
The advantage we see here after further consideration is of course more space for living area because a WC with shower or guest WC would be eliminated. Which, as noted by [USER=25027]@Maria16, certainly has its charm in terms of plastering technique.