Improve floor plan - how?!

I would also like to know where the 30,000 EUR more for "Stadtvilla" vs. gable roof (country) house come from. Not that the house provider has packaged a few more upgrades in that term. Because in the end, it's about a few more rows of bricks and then either a hip roof or pyramid roof vs. a gable roof. Which in my case only cost about 4,000 EUR more than the same house with a gable roof. For that little extra brickwork, when replacing the straight wall of a full floor, other materials are also used for the knee wall, so it cannot be fully charged; therefore, I do not believe that another 26,000 EUR could be involved.

I agree with my predecessors: first clarify how the terrain will be. Will it be filled up for you and if so, how? Is this just a suggestion of how it could be done, meaning you are showing that your actually sloping property can be "leveled" by filling it, you need to get the information about what is feasible and what is not, which means it is not always allowed to level a hillside property by building a huge wall. And if it is allowed, you have to know who pays for it. If it is just a suggestion of what COULD be done, then you pay for it - and that will be expensive. I would then throw the current design in the trash and come up with something that includes the slope in the planning - meaning a basement or partial terracing etc. In any case, a sensible design will look different. If you get the land leveled and prepared so that you can build directly on it, then the situation looks completely different. But I have the impression you don’t know that yet. And then no one here can help you. So for you: check the location! And do so definitively! And if you finally and definitively know what your property will be like, then you can consider how to deal with it – meaning what kind of house makes sense there. Right now you are building a cloud-cuckoo land house – that can lead to a harsh awakening. So educate yourself – and nobody can do that except you.

I would also like to know where the 30,000 EUR more for "city villa" vs. gable roof (country) house comes from. Not that the house provider has packed a few more upgrades into that term. Because ultimately, it’s about a few more rows of bricks and then either a hip roof or pyramid roof vs. a gable roof. Which for me "only" cost just under 4,000 EUR more than the same house with a gable roof. For that little extra brickwork, when replacing the straight wall of a full storey, the knee wall is also worked with different materials, so it cannot be fully charged; therefore, I don’t believe 26,000 EUR could be included there.

Thank you, we will clarify that today. I remember we had the city villa in mind, but discarded it immediately because of the disproportionately higher costs. But even if we switch to the city villa, the floor plan no longer seems optimal to me.

...I think that's good!

Additionally, maybe this:
It somewhat seems as if it has to be a decision between a one-story gable roof with a knee wall or a two-story city villa with a tent or hipped roof.
You can also put a gable, shed, or flat roof on two full stories.
Not that I particularly want to recommend any of these now, just so that when you start thinking about it anew, you don't assume false "limitations."

Clarify the height of the plot and who bears the filling costs.
- If the plot is still being filled, make sure it is suitable for foundation
- If it is not filled, clarify what you are allowed to do. Presumably, a residential basement is the cheaper solution.
Filling to this height costs a five-figure amount, and indeed a higher sum.

Look around on the internet for floor plans of this size, draw furniture to scale, let the tips here sink in, and do you really need that many rooms? For example, a dressing room – do you have totally different sleeping times, is it helpful, or is it only there because that's how it is usually done now? Put it to the test.
Do you need an office, or is it just a closet replacement-hanger-gamer-storage room? Can it be divided more purposefully? The sample floor plans are made so that they somehow fit four people and pick up on trends. But everyone is different. Go through your room program again. Not the number of rooms, but the 4m ceiling-high bookshelves, the sewing table, the 500 shoes that have to go into the wardrobe, the dog shower in the utility room downstairs, etc. Make sure that the bottlenecks that annoy you now do not arise again. For example, you want a normally sized washbasin in the guest WC because you regularly splash yourself at your parents’, you find the 85cm distance between table and wall too little. Then forget the recommended 80cm (which many don’t even observe in their show houses) and try 95cm which you find optimal.
Go through show houses again.
Pressure is a bad advisor.

...I think that's good!

Additionally, maybe this.
It somewhat seems as if it had to be a decision between a single-story gable roof with knee wall or a two-story city villa with tent or hipped roof.
You can also put a gable, shed, or flat roof on two full stories.
Not because I particularly want to recommend one of these now, just so that when you are starting to consider this anew, you don't assume false "restrictions."

Yes, this is now also the offer from Bien-Zenker. An upgrade to a city villa actually costs 30k more at Bien-Zenker. The walls are raised to 3m in height and the hipped roof is significantly more expensive. The suggestion is to raise the knee wall to 1.80 or 2.00 meters. Cost is about 1000 euros per 10 cm.