ᐅ Plot Layout & Orientation Single-Family Home with 160 sqm on a South-Facing Slope

Hello everyone,

My wife and I are actually about to request quotes for our construction project, but now I’m starting to have doubts about our basic planning.
I thought we had already considered and discussed all aspects and perspectives, and that the current approach was finally the only right one.
However, I am no longer so sure about that. Overall, I find it difficult to make the best use of the plot orientation.
Therefore, I kindly ask for your honest feedback.
How would you arrange the house, main entrance, and double garage?
What do you think is okay about the current plan and what is not?
I’m really curious to hear your thoughts :-). Thank you very much in advance!

Development Plan / Restrictions
Plot size = 650 sqm (7000 sq ft)
Slope = South, approx. 12.5% incline (rising from the street level)
Floor space index (FSI) = 0.4
Plot ratio = not specified
Building envelope, building line, and boundary = the plot is marked in red in the graphic below; the building line is shown with a blue dash-dot line
Edge construction = garage may be built on the property boundary; the house must have a 2.5 m (8 ft) setback
Number of parking spaces = 2
Number of stories = 3 full floors, i.e. basement + ground floor + upper floor
Roof type = tent roof, hipped roof, gable roof, or offset shed roof
Orientation = see plan below
Maximum height limits = street level is zero reference; max. wall height 9 m (30 ft) and max. ridge height 11 m (36 ft)

Homeowners’ Requirements
Style, roof shape, building type = tent or hipped roof, urban villa
Basement, floors = basement, ground floor, and upper floor; all full stories
Number of occupants, ages = 4; 2 adults and two children under 10 years
Space requirements on ground and upper floors = ground floor 88 sqm (947 sq ft), upper floor 78 sqm (840 sq ft)
Office: family use or home office? = both; home office to be located in the basement
Overnight guests per year = occasional, in the office
Open or closed architecture = rather open
Conservative or modern design = modern
Open kitchen, kitchen island = open kitchen with peninsula
Number of dining seats = 6–8
Fireplace = no
Balcony, rooftop terrace = no
Garage, carport = double garage with basement access
Terrace orientation = west, because as working professionals we prefer the evening sun. The terrace should also be as elevated as possible.
Garage orientation = therefore, the garage is placed on the right border of the plot
Garage driveway = we would like a maximum slope of 10% here (which will be challenging)
Neighboring buildings = right side is already built, very close with 2.5 m (8 ft) setback; left side is still undeveloped

House Design
Who designed the plan? Do-it-yourself + building planner
What do you particularly like? Difficult, it’s basically a big compromise.
What don’t you like? It’s a compromise.
Why? If the garage driveway slope should be <10%,
- the house has to be built deeper into the ground. This is not ideal because we would actually prefer a rather raised outdoor area. Also, the slope behind the plot would require more complex reinforcement.
- the garage driveway must be very long. A lot of surface would have to be paved.
Cost estimate from architect/planner: 700,000 EUR
Preferred heating system: air-to-water heat pump