Single-family house approx. 160 sqm flat roof - Optimization / Planning

No, I didn't do that! So, not just stuck a room on...

And sorry, but what am I supposed to make of the last sentence as the questioner...?

No, I didn't do that! So, I didn't just attach a whole room...

Not the whole room, but only the area portion of the additional room that was left over in total. But even that isn’t the Columbus egg of design technique, master yourself, right?

Because you are "complaining" in the other thread that there are few concrete suggestions for improvement, I have slightly revised your floor plan. Overall, I already like your second version much better; what still bothers me is this protrusion (even though it is now in the south) and the lack of space at the top of the dressing room.

What did I do? I aligned the ground floor and upper floor in the south exactly in the middle. This means the ground floor became smaller and the upper floor correspondingly larger. The total area remains the same, so it stays cost-neutral with your provider. To be able to reduce the area on the ground floor, I simply eliminated the space-consuming wardrobe on the ground floor and shifted the bathroom and utility room towards the entrance. You could hardly move in front of the wardrobe cabinets anyway. Utility room is now rather larger but more elongated. Bathroom also a bit bigger. Large wardrobe cabinet. Possible windows on the ground floor are indicated in blue. In the plan, the hallway looks narrow, but in reality that will look different because of the staircase. You could still have a storage room under the stairs. On the upper floor, I simply used the space for a larger bedroom and a bigger dressing room.

Looks good. I like it, although I would move one or two things for myself (door utility room or dressing room), but those are personal sensitivities. The window issue isn't too difficult here either - everything should fit well, including tension//harmony

: thank you very much for your thoughts and adjustments to the floor plan. I definitely like this version better.

Yesterday evening we spent a long time looking at the floor plans again and found a major disadvantage of this version for us: when you enter the open kitchen/dining/living area, you immediately "walk" straight towards the dining table/kitchen island. That feels chaotic.

Therefore, we took the other floor plan again and slightly changed the external dimensions. It would be nice if you could also give your opinion on this.
For us, the biggest disadvantage now: relatively small dressing room.

Sorry, I don't see it at all. To me, 's proposal is by far more balanced, harmonious, and functional. I don't understand the idea of walking towards the dining table/kitchen island at all. For one, take a look at the measurements, there is plenty of space. You are bringing the guest bathroom back to the center of the house. But it's your house, if you like it better that way... The ground floor is basically the starting draft...