Single-family house city villa approx. 180 sqm + separate apartment 70 sqm - open design

Hello everyone,
my wife (28) and I (34) are currently finalizing the planning for our single-family house + a granny flat.
In the past, I have read a lot in this forum to get inspiration to plan the perfect floor plan for us. I hope the information below is sufficient, otherwise I am happy to provide further details.

Brief explanations:

[*]Plot 775
[*]The granny flat is needed because otherwise we would not get the plot. The current owners of the plot (old building that must be demolished) will live in the granny flat and pay us monthly rent.
[*]We would like the cellar stairs in the storage room, but that is probably too tight. Therefore, we have possibly planned the cellar stairs above the office. Exact dimensions and feasibility are currently being checked by the architect.
[*]At the entrance, there is a guest wardrobe, the family wardrobe will be realized as a built-in closet in the hallway to the garage.
[*]The storage room in red is correct, we had to move the stairs a little to the right :)
[*]Doors are currently not all drawn in, sorry.
[*]Laundry chute planned in the master bath/children’s bath.
[*]Orientation was not quite right, I had to adjust it a bit afterwards :)

As soon as the first draft from the architect is available, I will of course upload it as well.

Development plan/restrictions
Plot size: 1028 sqm
Slope: No
Site coverage ratio: 0.3
Floor area ratio: 0.6
Building window, building line and boundary: 15*~28 m
Edge development
Number of parking spaces: 1 per residential unit according to the development plan.
Number of floors: 2 or 1 for granny flat
Roof type: Hipped roof or flat roof
Style:
Orientation: South, South-West
Maximum heights/limits:
Further specifications: open construction, 2-storey

Requirements of the builders
Style, roof type, building type: urban villa, hipped roof
Basement, floors: yes, possibly partial basement
Number of persons, age: 2 adults (34, 28), 1 baby, another child planned
Space requirements in ground floor, upper floor: GF – living, kitchen, storage room, office, WC; UF – child 1, child 2, parents, dressing + storage, parents’ bath, children’s bath
Office: family use or home office? Home office
Overnight guests per year – 0
Open or closed architecture: open
Conservative or modern style: modern
Open kitchen, cooking island: open kitchen + island
Number of dining seats: 6
Fireplace: no
Music/stereo wall: 5.1
Balcony, roof terrace: no
Garage, carport: double garage
Utility garden, greenhouse: maybe later
Further wishes/special features/daily routine, also reasons why this or that should or should not be

House design
Who planned it: DIY, architect
-Builder planner
-Architect
-Do-it-yourself
What is especially liked? Why? Open construction, orientation, cantilever stairs
What is disliked? Why? Access to cellar not ideal so far
Price estimate according to architect/planner: 600k
Personal price limit for the house including equipment:
Preferred heating technology: geothermal with ring trench, BKA, underfloor heating, ventilation system

If you had to do without, on which details/extensions
-could you do without: gallery
-could not do without: open construction

Why did the design turn out the way it is now?
Own wishes and ideas, research of many floor plans. Granny flat separated from single-family house.

What is the most important/basic question about the floor plan summarized in 130 characters?
Is the room layout sensible? Clever ideas? General feedback on possible problems. Open criticism welcome, I appreciate every hint.

Many thanks in advance.
Tobi

The house is too small to afford the luxury of a second stairwell for the basement stairs, just so a cantilever staircase can stand out as a sculpture. You will surely find more suitable gimmicks to impress your circle of acquaintances with a unique house. Otherwise, as is "usual" from me, first of all thanks for the classic analog self-drawing.

The granny flat is needed because otherwise we won't get the plot. The current owners of the plot (old building that has to be demolished) will live in the granny flat and pay us monthly rent.

In my opinion, the concept of the retirement house should become much more common. Besides, I would check whether a compensation of the purchase price and the value of a right of residence might be more favorable for all parties involved.

Thank you very much for the quick feedback. Cantilever is a consideration, we are more concerned about the straight staircase in the open living space. We have already reviewed the scenario with the offset, have had several rounds with the notary and another tax advisor. Any other suggestions?

Placing the basement stairs at the end or to the side of the straight staircase shouldn't really detract much from the open design, right? If it is meant to remain completely open, one could just do without a basement door? Just throwing this out there as a suggestion:

I'm not sure if I understood you completely. What do you mean by next to the straight staircase?

Like in your picture would be our dream, but then you look directly down the basement stairs when sitting at the dining table :/

Our dream scenario would be just like in your picture, but then you directly look down the basement stairs when sitting at the dining table :/

The view of the young lady’s tatscher on the glass wall would reliably distract me :-(