Floor plan: ~150m² single-family house bathroom arrangement on the upper floor

I do not want to go any deeper into the "Jane" topic, however.

I have long noticed that - that is exactly why I so persistently point out that Jane might see it differently.

What is your basis for the considerations now? The last version of the ground floor you posted?

Don’t get lost in too much rationality and too many considerations....
In the end, you have a separate, closed room for every purpose and have thus built a house from 1900.

Nothing has changed in the plan yet, but I am mentally considering removing the ceiling in the east (shower), creating a kind of light space with large windows from the ground floor to halfway up the upper floor.

Now it’s getting wild. There will be no open gallery upstairs. So just a reduction of living space upstairs and downstairs in favor of a narrow shaft.

What is now the basis of your considerations?

That will be the study, because

I would like to keep the idea of the large study for now

Gut feeling says the ground floor has developed for the better, and the utility room can also be retained in full size.

For God's sake: at least one person said it is a botched improvement. I think so too. And the moderate participation in this thread I interpret from my many years of experience as no one can find anything good in these bad designs. Even worse is that you do not focus on relaxed and functional living, but only on your study. This planning does not work like that and neither does the house. ... one has the feeling as if every post from us is wasted effort. And you do not take the advice either!

So far, I have tried to implement as many constructive suggestions as possible, such as

[*]more storage space
[*]more utility room
[*]more wardrobe
[*]ground floor bathroom arrangement
[*]remove the nose at the AZ entrance (behind the stairs)
[*]postponed the granny flat (large AZ stays for now)

Currently, I am still working on it but have nothing to show yet

[*]upper floor light space in the east
[*]upper floor hallway in general, seems to remain as usual (about 1x2m)
[*]upper floor bathroom arrangement

My experiences with the living room:
It stays empty all day (work, then garden)
people meet for dinner (dining room not available)
father stays for watching TV
mother comes back for the crime show
son stays upstairs at the TV/computer

That's how I grew up and that's how I know it.
What else should you do all day in the house with 4000m² garden?
Yes, I know it sometimes rains, but so far about 20m² have been completely sufficient. For the life of me, I still can’t imagine the use of a 50m² "ballroom" living room that also needs to be heated to a comfortable temperature.

Without knowing the community here, I would say that people quickly lose interest in the thread if every second post heads towards marital status..
Maybe it also has something to do a bit with the thread title.

Father stays for watching TV Mother returns for the crime show

Okay, that explains some things, then we are apparently from different worlds ...

Son stays upstairs at the TV/computer

... and Son now wants to keep it that way when his new room will be a whole house next door (?)

I would say that you quickly lose interest in the thread when every second post goes in the direction of marital status..

The impression only remains with you because you deliberately dismiss the other point, which is also essential (certainly for your house), namely to at least roughly conceptually consider the development of the two additional building plots in the back field.

I still cannot for the life of me imagine the use of a 50m² "ballroom" living room

No one is saying that. But a house with 139sqm or so should certainly be suitable for family life.

My experiences with the living room: It stands empty all day (work, then garden) People meet for dinner (no dining room) Father stays for TV Mother comes back for the crime show Son stays upstairs at the TV/computer

Strange family peculiarities. Yes, maybe that fits the 90s, but family life and daily routines fortunately look somewhat different nowadays, thanks to enlightenment and emancipation. Sometimes people actively do something together in the house... not just "meet," "stay," and "come back."

That’s how I grew up and that's how I know it.

Then it’s about time you start dealing with designing living spaces in the house and not just an office, enclosed by too tight living spaces and bedrooms you come back to, so that you don’t make the same mistakes as the family patriarch back then, who only came back to read the newspaper until the food was on the table. Are you still living or are you truly alive?