ᐅ Floor plan design for a new build with two full stories plus attic conversion

Development Plan / Restrictions
Plot size: 654 sqm (7,041 sq ft)
Slope: no
Site coverage ratio: 0.4
Floor area ratio: 0.6
Building envelope, building line and boundary
Perimeter development
Number of parking spaces
Number of floors: 2 full stories
Roof style: gable roof 28°
Architectural style
Orientation
Maximum heights / limits
Additional requirements

Homeowners’ Requirements
Architectural style, roof style, building type
Basement, floors
Number of occupants, ages: 2 persons, 28 and 26 years old
Space requirements on ground floor and upper floor:
Ground floor – living room, kitchen, pantry, utility room, guest toilet, fitness room
Upper floor – bedroom, child 1, child 2, home office, bathroom, storage room
Attic –
Office: home office
Overnight guests per year: 2
Open or closed layout: open
Traditional or modern construction: modern
Open kitchen, kitchen island: yes
Number of dining seats: 4–6
Fireplace: no
Music / stereo wall: no
Balcony, roof terrace: no
Garage, carport: yes
Utility garden, greenhouse: no
Additional wishes / special features / daily routine, also reasons for preferences or exclusions

House Design
Planner: do-it-yourself
What do you particularly like? Why?: The space behind the stairs is used as a pantry / storage room.
What do you not like? Why?:
The living room feels cramped because of the fitness room; overall somewhat dissatisfied with the layout but not sure what is missing.
Hallway possibly too narrow? Especially in the entrance area.
Price estimate according to architect/planner: 430,000
Personal price limit for the house, including equipment:
Preferred heating system: underfloor heating

If you have to give up, which details / extensions
- can you do without:
- can you not do without:

Why is the design as it is now? For example:
Because we are building a house attached on the left side, no windows can be placed there, but of course we would like to have windows in all rooms. We can do without windows in storage rooms and pantry.
The staircase is meant to allow continuous access from ground floor to attic without taking up much space. In general, we would like to use as little space as possible for corridors.

What is the most important / fundamental question about the floor plan in 130 characters?
The biggest issue is that we cannot place windows on the left side of the house, which limits room distribution.
We are also unsure if the staircase is the right choice for saving space. We tried to position it so the attic exit is relatively central.