At this point in time, however, we probably would no longer be willing to make such massive floor plan changes.
Understood. However, I had to read everything again and thus "reconstruct" the discussion for myself ;)
It's just not smart to ask about the floor plan again after the building application.
Quietly, I criticize the staircase, which was deliberately not placed above the basement stairs, but also did not disappear into an uncomfortable hallway.
By the way, I am quite aware of the reason for relocating it out of the "family area"... later separation into 2 apartments... but paying this price for it? The guest WC is not age-appropriate in its size anyway, and where are the grandchildren supposed to sleep later or hobbies be pursued?
We also still need to consider a separation from the dining area to the shower/WC (line of sight), possibly with furniture
Instead, the throne is still the centerpiece of the dining area and will be the focal point of family life in a 5-person household. Guests linger here.
And now you suggest a piece of furniture for that.
Then set it up as suggests in #57 – that also makes the room a bit special.
Also, I was a bit puzzled, because I mentally placed the living room in the east (I think I once read that) and also found it sensible since there is no access to the garden in the east, but there is in the west, and also the larger portion of the garden, so you would expect daily life to take place here. Now you have the living room in the west... and somehow "only" _one_ terrace access. I would probably grant the west side floor-to-ceiling windows on the ground floor, and suggest railing windows in the bathroom and children's room upstairs.
The bathroom window might collide with the shower partition. If child 3 gets a niche under the stairs, then I would grant the shower even more space and extend it further.
I would not have arranged the carport/garage next to the neighbor's garage, but rather in the northwest near the street and with a short driveway turning right, i.e., at the height of the guest room – with a pergola that connects garage/carport and house, you get a cozy and sheltered spot on the west side for evenings. But maybe it also makes sense behind the garage where it is currently planned.
By the way, I think the bathroom is very nicely furnished. If you still mediate the bathtub a bit and integrate it nicely, and store the white appliances in a cabinet, you get a nice zoning.