Semi-detached house with unequal halves = different floor plans

Preliminary remark: the larger half in the north (right side of the plan) is intended for own use. The smaller "half" in the south (left side of the plan) will be sold. For the half for sale, there was only the requirement "meaningful room usage for 3, max. 4 people." Therefore, I will go into more detail about the own half here.

Because it is not apparent from the floor plan excerpts: the own half is 8.75 m wide and 9 m deep, the half for sale is 6.10 m wide and 9.65 m deep (external dimensions).

Development plan/restrictions
Size of the plot: 479 sqm, 23 m wide, 20.80 m deep
Slope: sloping to the southwest, approx. 3 m diagonally NE-SW
Site coverage ratio: 0.35
Floor area ratio: 0.7
Building boundary, building line, and limit: 3 m building boundary, no building window
Edge development: neighbors’ garage on the south border
Number of parking spaces: 2 per residential unit
Number of floors: 2 full stories
Roof shape: SD 25-45 degrees, WD, half-hipped roof, VPD
Maximum heights/limits: max. ridge height 9.50 m
Further specifications: none

Client requirements
Style, roof shape, building type: modern, straightforward, simple building shape, gable roof
Basement, floors: no basement, 2 full stories, attic
Number of persons, age: 3 (2 adults + toddler, no more) / 2nd semi-detached house half should be designed for a family with max. 2 children
Space needs on the ground floor and upper floor own half:
GF: guest WC, cloakroom, large open living/dining area, open kitchen, utility/technical room
UF: large children's room, bedroom, family bathroom, laundry room
Attic: studio (office/guest room/hobby room), shower bath
Office: family use or home office? both
Guests per year: approx. 20 nights, 1-4 persons
Open or closed architecture:
Conservative or modern construction method: modern
Open kitchen, cooking island: both
Number of dining seats: 8
Fireplace: undecided
Music/stereo wall: no
Balcony, roof terrace: no
Garage, carport: no, parking spaces
Utility garden, greenhouse: no
Further wishes/particularities/daily routine, gladly also reasons why this or that should not be: requirement for the own half was a half-landing staircase, not accessible through the living area. Desired was a design away from the "classic semi-detached house standard", also externally. No "entrance corridor."

House design
Who is the planner: architect

What do you particularly like? Why?
Own half:
- Split level to the living area, resulting in a high ceiling height in the all-room and utilization of the topography
- large cloakroom/storage area
- storage space under the stairs made usable
- utility room on the upper floor
- large children’s room (is intended to be swapped with attic studio when child is older)

Half for sale:
- ?

What do you not like? Why?
Own half:
- Utility room only accessible from outside (wtf?!)
- All-room quite "small"
- Kitchen small, no island, dining area only for 6 persons
- Guest WC wastes space
- overall few/small windows
- arrangement of family bathroom: shower exit right in front of door, toilet directly next to sink
- unfortunately no dressing room
- attic bathroom: shower exit again right in front of door
- attic studio window: tiny arrow slit to the west (the side with the really great view), but 2 roof windows instead. (my next wtf moment)

Half for sale:
- no second shower bathroom
- upper floor bathroom tiny, no shower
- boring floor plan
- 2nd room attic without window?! (again wtf moment)

Price estimate according to planner: just still within budget (would prefer not to discuss figures publicly due to sales plans, thank you for understanding)
Preferred heating technology: preferably geothermal, if still within budget

If you have to give up something, which details/extensions
- can you do without: geothermal, attic bathroom (would initially only install the pipes, finish later)
- cannot do without: half-landing staircase

Why did the design turn out as it is now?
Our requirements regarding the room program have been largely implemented.

Which wishes were fulfilled by the architect?
Height and depth offset of the semi-detached halves, stair not accessible from the living room, utility room on the upper floor

What makes it particularly good or bad in your eyes?
Arrangement, position, and size of the windows cause me great question marks.
Furthermore, I cannot understand why the plot width is not fully used. 3.50 m on the sides are enough for parking spaces; for the half for sale, we would leave 3 meters on the side so as not to take too much garden at the back. The very first study was much more narrow, and we had already pointed this out. Now in the north, it is still 4.12 meters and in the south 3.93 meters on the side. Why?? Dead space next to the cars that we won’t use, unlike garden space to the west.

What is the most important/basic question about the floor plan summarized in 130 characters?
What can we improve?

Maximum attachments reached, therefore here is another floor plan.

Just briefly regarding your "HAR only accessible from the outside - wtf?": it has to be that way because the technology is also for the other half of the house. According to § 5 Abs. 2 WEG, rooms that serve communal use (like technical rooms) cannot be private property. The neighbors must also have access without always having to depend on you being there, after all, it is also their technology. You also have a utility room upstairs.

Just briefly to your "HAR only accessible from outside - wtf?": it has to be that way because the technology is also for the other half of the house. According to § 5 para. 2 WEG, rooms that serve communal use (like technical rooms) cannot be part of individual ownership. The neighbors must also have access without always relying on you being there, after all, it is their technology too. You still have a utility room on the upper floor.

No, the south half has its own technical room in the attic, house connections are there in the guest WC. The halves of the house are connected separately, each gets its own heating technology etc. The greatest possible separation is extremely important to us. Hence my wtf...

I just spontaneously thought that I would pay very close attention to the decoupling of the neighbors' stairs, especially because your bedroom is directly adjacent to it. If the neighbors go up and down the stairs while you are sleeping, you shouldn't (have to) hear anything.

No, the southern half has its own technical room in the attic, house connections are located in the guest WC there. The halves of the house are connected separately, each receives its own heating technology, etc. The greatest possible separation is extremely important to us. Hence my wtf...

Then I take it all back, I had overlooked that.