Single-family house design with a gabled roof at the edge of the construction area

Stairs to the north, we could no longer get into the attic.

With 150 KS, yes you can. You don’t plan a landing staircase to the attic, but rather a simple 2/4 quarter-turn staircase, and that fits over the landing staircase.
You’ll just have to accept one thing if you don’t want or can’t spend on a star architect or €100,000 more for complicated (incomprehensible to laypeople) architecture.
I also see the west side as dispensable and would use the entire south side. That way you at least have sun in the living rooms during the dark season.
For the evening terrace, you can still stroll at some end of the property with a glass of wine in your hand.
I would also rotate the rooms similarly to haydee, and personally, I would design the entrance area in front of the front door as an inner courtyard if a carport is possible at the front by the street. With your 11-meter house depth, 6 meters of garden remain on the south side, minus 1 meter for the hedge, leaving 5 meters that are enough for a south terrace and should also be planned accordingly.
In the bathroom, a washbasin at 150 doesn’t work at all. Best to put the toilet next to the tub or under the slant, the shower one meter wide, and the wash area at the window.

Hello RotorMotor,

I am definitely an advocate of the beautiful view and not the cardinal directions. Nevertheless, it is nice when a lot of light and also some sun comes into the house. I myself also have an east garden with a view towards the forest and therefore an east orientation with living and dining rooms. I love it, it is simply incomparably beautiful. My kitchen faces south (= neighbor) and also has a west window (towards the street). However, here the sun only comes in during the summer because the E+1+D houses (which are more than 20 m (!) away) block the sun in winter.

Regarding the location of the house and terrace: I would not sit with the terrace facing the street if I can sit completely undisturbed in nature at the back. Therefore my suggestion is to place the terrace at the top right corner, there you get east, south, and in the late summer also west sun. Only in the afternoon, when it is usually too hot anyway, your house casts a shadow. I would plan an additional seating area at the top right property boundary anyway (for plenty of sun all day).

I have adjusted your floor plan according to my ideas (this is how I would do it if it were my house). First of all, 2 full floors instead of a knee wall. I have spread out the ground floor because it is the main living area and in your draft it would be definitely too small for my taste. For me, only an open space, large kitchen with plenty of storage options and guest WC, small storage room under the stairs. Upstairs, however, a small utility room. In the attic (not drawn) a small guest room and office (possibly as one room) and heating. Additionally, storage space under the slopes. Two dormers bring more usable space here.

What I like about my draft: entrance from the front and not from the side, where the postman and children always scrape past the car parked in front of the carport. In the kitchen, the corner window catches the south and west sun + view towards the garden while cooking. Living room with a view into the forest and light from all 3 directions. Dining room with view towards the garden. Through the large west window by the stairs and the large glass door from the hallway > open space you also get a lot of light from the west. Large wardrobe. Spacious entrance area.

The upper floor stands about 0.7 m above the ground floor on the south side and forms the entrance canopy. Children's rooms face south, parents towards the forest in the north. Utility room directly adjacent to the dressing room.

Only downside: your guests have to sleep in the attic and shower downstairs. But it is your house, so I would always put guests on priority 2.

Well, maybe I could at least give you a few suggestions!

I am surprised that nobody is bothered that we are discussing self-drawn floor plans here, that was a no-go until now

No, it was never a no-go. Only some were so good that they are only suitable for the bin.

I'm surprised that no one is bothered that we are discussing self-drawn floor plans here, that was a no-go until now

??? - on the contrary: I always explicitly praise it when someone dares to scribble themselves instead of presenting some "3D" clicky-colorful illusion of a sadly non-functioning house as "almost final".

Kitchen - if you want to accommodate 4 side cabinets each 60cm, the niche should be about 245-250cm raw construction measurement, so that after plastering / unevenness / lack of squareness and annoyance and frustration it also fits.