General criticism of architecture, spatial layout, exterior appearance

I find the design successful. But the discussion about the plot makes me doubt. And I already notice that the questionnaire was once again not filled out, so important information is missing that now has to be gathered and remembered over dozens of pages of thread.

How big is the plot? Where is the house located within the building area? Is there a slope? Floor area ratio, plot ratio, development plan, etc.?

I would, for example, ask myself whether it would be better to live on 2 levels and build a basement instead. Given the apparent slope location (?), one half of the basement could perhaps be converted into a lower ground floor. Parents completely on the ground floor and the children's rooms alone upstairs. But one does not know the areas and conditions.

: Wasn't there something like that with you too, which is why the stairwell has the sloped roof?

Yes, we had to put a shed roof on the cube by the roof terrace because the woman at the building authority argued that otherwise it would be a 3rd full floor.
In the meantime, we strongly doubt her argument because she only considered the area of the cube for the assessment and not the entire floor area.
If we had challenged that, we probably would have had a chance to get it approved.
But now it’s already built and I can live with it.
Except that we might want a sauna and standard sizes don’t fit because of the sloping roof...

Why distorted 3D drawings? The drawings are based on the cadastral maps etc. The plot is 16x28 and the building window is 3m from the building boundary. Since the street is about 130-150cm above the ground, this must be filled in, which is also marked.

The problem here is: for the application, the current terrain level counts. To the (I estimate now) 6m height of the lower two floors, the 1.5m fill is added and the top edge of the first upper floor is 7.5m above the original level, which can be tight with 3m at the boundary. I believe a boundary distance of 0.4*h applies here in Saxony. It would therefore be important to fill in first to raise the boundary to the later level. Here again, your neighbors have to cooperate. If they want to use the slope at the back for a usable basement, their interest in a level increase will be limited. Consequently, you have to work with L-walls, which in turn must also be checked for approval eligibility.

Even if one seldom sits by that window, it still contributes to the individual character of the house. You can use unusual masonry, after all, stones come in several compressive strength classes.

Tastes are known to differ. I don't like this individual touch. I would rather have large-area windows across the entire front.

Just to add my two cents: Floor-to-ceiling windows in the living room, and then half of them are immediately blocked by a sofa. This not only obstructs the view outside, but the blocking sofa itself then offers the alternative view of ... a wall with a black box.

This is not an isolated case, but is often done like this.

My personal suggestion would be to rotate the sofa 180° with a double view outside: from the sofa itself and from the dining room without an obstructed view.

Solution for the flicker box, of which probably won’t be many sold in 10 years anyway: short-throw projector / laser projector on the ceiling above the window with a retractable screen.

I don't like this individual touch.

Well, with an individual touch, that's not a bug, but a feature. Mind you, personally I don't like the whole house. But as far as I know about other tastes, it is consistent in its conception. So I find it good "from the real estate agent's perspective," although I myself prefer to live differently. In the - especially unintended - case of commercialization, it is simply advantageous if a property appeals to people with above-average incomes. And with just a pillar between the windows as if they were garage doors, I see this less so than with the bay window. In this case, besides the taste of potential buyers, I would rather reduce the color contrast of the facade for my own taste as well.