Floor plan single-family house approx. 160 sqm - suggestions for improvement?

Yes, the plan is oriented north. We chose the roof direction (?) so that the roof surface faces south and we can align the photovoltaic system well there. On the right is the access path, exactly.

But that does not fit at all with the windows etc. And the gallery window would have a maximum knee wall height minus lintel. From that, one would have nothing in the upper floor hallway. Or am I just having a mental block?

But that doesn't match the windows etc. at all. And the gallery window would have at most knee wall height minus lintel. You wouldn't have anything of that in the upper floor corridor. Or am I just having a mental block right now?

The north arrow is probably placed incorrectly.

The upper floor is 9.42 deep, the ground floor only 9.00 meters, according to the specification of the wall dimension on the left.

No, kbt09 is right about the orientation (and was faster and smarter than me with the rotation). We would plan a gable for the gallery window. The exhibition house of Weberhaus in Wenden with a staggered shed roof shows this quite well.

The upper floor is 9.42 meters deep, the ground floor only 9.00 meters, according to the wall measurement on the left.

Then I notice: one exterior wall measures 7 meters including exterior walls at the corners. At 6.20 there is an interior wall. So 6 meters remain, which are divided between the living room and the office. Hm...

I would like to point out again that something like this needs to be taken into account. A program is being used here, and like others, the delete key is no longer pressed there. Next time use graph paper, then you'll also have an overview of the width of the living room.