Ground floor approx. 100 sqm, upper floor expandable (planned bathroom, 2 children's rooms, 1 storage room)

Then the floor plan is set for the OP and he will no longer be receptive to any arguments.

He actually was right from the start: a 90-degree rotation of the roof, but no revision of the floor plan – whether sensible or not. But this "I actually want it differently, but it should not be changed" doesn't lead to a fruitful discussion.

Sometimes there is also a feeling of not wanting to, without knowing exactly why not... then it has to sink in a bit.

Exactly – I don't see that the OP is letting anything sink in – I just notice a "don't want to."

Wasn't that in combination with a pass-through into the living room? Honestly, if you put up a wall there, access the kitchen via the hallway, and then still come up with the argument about smells, any further words here are pointless.

Yes. But honestly? In combination with a room door, smells (I call them scents, provided they come from the kitchen) always spread into the rest of the house. No idea if high-tech Bora is any different. I don't have one either, because I don't see the ratio of advantages to price. Mind you: in our case, you can smell for two hours that there is fish or something fried. My guests are happy when they enter the house because it smells so good. When washing up (pot and knife), you open windows for about a minute – that works.
A kitchen door in front of the stairs obviously also makes the OP’s whole way of thinking highly sensible.

From the outside, by the way, I find the house quite charming.

I actually referred to odors in relation to a pass-through. What I did forget to mention, and which then makes my position somewhat unclear to you, is that I am/was afraid that an additional window in the utility room would take up too much wall space for my ideas. However, these concerns could be resolved by another window shape. The same would apply to the bedroom, as then not everyone would be able to look into the bedroom at first glance. We could also imagine not taking a rectangular window, but a flat, elongated window. This way, a bed/shelf or similar would still fit under the window. If there is such a window on both sides, it is also visually acceptable.

This way, the staircase could also not only be straight, but have a slight bend.

Why don't you consider making the utility room accessible from the hallway? The kitchen benefits from more space and is not a hub for doing laundry. Also, the kitchen then loses its current function as the second hallway. Entrance to the utility room, kitchen door, and only then into the hallway... The smells won't immediately spread into the utility room and onto the freshly washed laundry.

Laundry room and pantry connected to the kitchen and dining area makes ergonomic sense. ....When you slaughter a pig and make liver sausage. [emoji3]

Laundry room and pantry connected to kitchen and dining area make ergonomic sense.

But not if the utility room is also an entrance. This turns the kitchen into everything but a cozy spot.
It’s just like when a builder says: I’m counting on less repayment, everything left over goes into special repayments. Also, the outdoor areas will later be done with the money that comes in. Little by little... oh yes, and we’ll do everything later anyway. All unplanned bottlenecks rest on a bit of Christmas bonus.
The same will happen here with the kitchen: combining utility room with kitchen, how practical. The housewife can just stay in her corner. Entrance? We’ll route it through the utility room. Eating? Smells, so preferably in the kitchen. Hello? Maybe one should give the kitchen 20 to 25 sqm and shrink the living room. That makes more sense.
The use of the house here is very … unbalanced. There are friction points that ultimately don’t make you happy.

Strange...our neighbors, eksjö hus, back door goes into the utility room and from there into the kitchen. We Specht Fehmarn plus all houses from him that I know, back door, utility room, kitchen. Kinder, Team massiv, back door, utility room, kitchen, Concept vario Ahrensbök, Stollhaus Schuby, etc. all do it that way, those who are successful here. You come in, take off your shoes, and stand in the kitchen, are immediately offered a seat and a bottle of Holsten Edel in your hand. To make it nice and cozy, my wife, as you know Yvonne, even put a sofa in the kitchen. Karsten