Single-family house ~180m² in the city with a view of a nature reserve

Maybe the two should have preferred to seek advice here in the forum

It's not about this OP or any other OP adopting the wishes and ideas of others.
It's about having listened to / looked at every objection / idea presented once and then deciding: Thanks, but no thanks.
The comments from forum users are only meant to sharpen awareness for / against decisions - nothing more.

Yes, absolutely, that's exactly how it should be.
My "note" referred exclusively to the private/personal environment, where the directly (often painfully) noticeable comparison happens more often. Envy and the actions resulting from it are often closer than one thinks or wishes.
If your gardener shows up with the Porsche, I don't care; if you were my neighbor or cousin, I could beat you up for that—

Completely independent of the floor plan (something is bothering me, but I cannot yet effectively communicate what it is): The reference to [Paragraph 34] is important. Have you ever been to the responsible building authority and inquired what you are allowed to build there?

In a burst of creativity and being stuck on your own floor plan, I'll just give you an idea. Not perfect, but just a food for thought. In this design, you could narrow the hallway / entrance area and add the gained width to the living room. You only have one door to the utility room in the hallway; the long wall can be nicely used to place, for example, a small couch where you can sit down to put on your shoes. The staircase with the start from the living area is daring and must be intentional. In the upper floor, my idea has a flaw because a void space arises behind the staircase. I did say: not perfect. With the changed staircase, you would have two larger bathrooms each. The walk-in closet remains a bit zigzag. Maybe place the bed against the right wall and move the entrance from the walk-in closet to the bedroom to the left side. Above the bed, maybe a big skylight? You also have to see it from outside once. If you have added more width to the ground floor downstairs, it will positively affect the upper floor's master section. Just a few thoughts...

We would greatly appreciate any tips and opinions on the attached drafts. Many thanks in advance.

After De

It is probably more related to the fact that I do not design houses full-time and therefore have not yet developed a feel for the plan size and the actual room size. However, I do not recognize the empty spaces/filler rooms to the described extent.

that's how it is! Some can play Tetris, some cannot. Clubs and sticks from me are always reluctantly accepted. Therefore, here is a formal note: get yourself an architect, give him your desired program, and then let the professional draft be discussed. Better that way.

I also find the superstructure somewhat bulky and unappealing. --> Is that a matter of taste or a neutral assessment?

It is a neutral impression, expressed by me based on objective criteria, visual design rules, and subjective impression.

If you have read all the pinned posts, you know what cannot be accommodated in garages.

Now I know what bothers me about the appearance. Hard to put into words. Bauhaus for me is bright, open, nice proportions, preferably also offset and not just a simple townhouse with a flat roof. Here, dark living spaces, large extension (industrial look). It’s simply unbalanced.

First clarify what you are really allowed to build. It would be a shame if it now needs a pitched roof just because the neighbors have one. That was one of our first steps, catalog with houses, site plan and off to the building authority. We want a house like this, we want to build there and demolish this and that. Yes or no? Can we plan it like this? With the old mayor, the house would not have been approved like this. Neither the ridge direction, the size nor the location. It stands out from the crowd.

After De

With me, the sentence is very often cut off.
It is supposed to mean: after your answer and the justifications, you do not want any criticism.