Unfortunately, the staircase is not dimensioned, I also consider it quite narrow, 14 marked steps. When rotated, a wall can be omitted just the same.
The small bathrooms are about 180 cm wide .. or? In the end, more than 80 cm do not remain for the toilet (plaster, tiles, shower enclosure, etc.). This bathroom layout is also often chosen in hotels .
On the west side on the ground floor .. I think the kitchen should be planned because a window would also be quite useful there, then the dining area window and then you can see how it harmonizes with the windows in the basement. Both windows are currently drawn with a height of 112 cm, unfortunately without any view. If the terrain is as I imagine it, then the window in the study will have to be less high.
Should the windows on the south side of the ground floor (living room, children’s room) really be divided into four parts like that? Lower element fixed glazed? Or fall protection? There is a sofa planned in front of it in the living room ... why not simply windows with a normal sill height? Then you can also always better arrange a desk etc. in the children’s room.