Floor plan design for single-family house - Finalization

One more thing:

so it is actually like this:
the house was planned from the outside (what fits into the existing structure here and uses the maximum size possible).
and then we try to accommodate what we wish for (EG: large living-dining area, open kitchen, fireplace, study, and in the DG: 3 bedrooms).

Is the parcel 73 also dimensioned with building boundaries?

I would probably put a more or less standardized (in terms of floor plan) single-family house on it, in appearance and harmony with the existing building. Kitchen where the living room is now. Small office. The guest room would be relocated to the basement with a slope and outdoor access. Omit the extension. The floor area ratio will then also benefit the size of the main house. For the perceived separation, possibly position the house crosswise (if there is enough space) or set a nice hedge.

Is the plot 73 also measured with building boundaries?

I would probably put a more or less standardized (in terms of floor plan) single-family house on it in appearance and harmony with the existing building.
Kitchen where the living room is now. Small office.
Guest room would be moved to the basement with a slope and outside access.
Leave out the extension. The floor area ratio then also benefits the size of the main house. For the perceived separation, possibly place the house crosswise (if there is that much space) or set a nice hedge.

Hey Yvonne,

so we have to keep the 3m distance. There is no building window, but in terms of depth we have to align with house 19a (we would like to go deeper into the property, but it’s not possible...).

If we do it without the "extension," then the new house would be 4m away from the old house on the west side, so it would also block some light.

Why I don’t want to swap living room/kitchen I’ve already written (the architect’s suggestion was the same as your proposal...).

But overall, it’s certainly worth considering making the house 2m deeper (if without extension, that would be about 15/16m x 9.75m in dimension).
Then you could build a smaller office/room and relax the whole thing a bit.

so it is actually like this:
the house was planned from the outside (which fits into the existing structure here

I didn’t mean "positive" in the sense of "marked the maximum framework and utilized it" – but in the sense of "the rooms ended up where the facade wanted them."

and the maximum possible size was used).
and then tried to accommodate what we wish for [...].

What use is it to exploit an area calculated by square meters, but then fill those square meters again with empty calories – that was certainly not included in "what we wish for," but apparently that is what came out of it. The highest share on the ground floor is those circulation areas that cross the rooms in an awkward dance. Therefore – and not because of any aesthetic shortcomings – my strong doubt about the planner’s training.