L-shaped floor plan - What is your opinion?

I have no suggestions for a plan that has no dimensions nor apparently involves a castle in the air here. Strangely enough, I have to join your experience with the BUs on this. Namely:

Regarding the budget: Well, we are still flexible. We first wanted to wait and see what the offers say. It will probably also be a huge difference between KfW40+ and KfW55.

You cannot plan elaborate statics, building type, or envelope if the budget is limited. Any bay window, oriel, or slanted wall costs money. A lot of money. If two roof terraces are roughly estimated at about 30-40,000€ including complex roof structure, energy saving regulations, sealing, etc., then you should know in advance whether that would be feasible.

Hip roof and knee wall: We are still completely open there. If the upper floor is set back (regarding the alignment of the outer walls with the ground floor), then we could also imagine the upper floor as a flat roof?

But that is important for the staircase location as well as door placement.

First the floor plan, and then we will see what 1. looks good in terms of knee wall and roof shape and 2. is affordable.

Of course the floors belong together. But can you please simply accept that we are not that far yet? The ground floor has to be done first, and from that we derive the upper floor for us.

NO!
YOU should accept that a design of a single-family house is not just a drawn 2-D sketch of one floor on a sheet of paper.
Exterior walls have to carry load, the building envelope as well as the facade shape the view. Basically, the staircase is first set as an element and it must function.

Basically, you have to say that we get up together every day and also go to work together. But on weekends I do like to sleep longer than my partner from time to time. So only I would have a 'problem' with the floor plan.

Habits will change over time.

The division of the rooms except the parents’ area as mentioned is sensible, but a completely different layout would also be feasible.

There is a lack of storage space. Cloakroom. I do not see daily work or daily use here.

The shell construction of your corner corners costs about as much as a shell construction rectangle with a 170 sqm floor area.
Plus roof of the outbuilding, beams, possibly thicker ceiling.

About the floor plan:
The staircase seems a bit narrow.
How is the wardrobe supposed to be designed if the walking direction has to be changed due to the roof pitch?
I find the wardrobe unfortunately placed. You walk with socks through the dirty area.

Dining area: please draw the table with occupied chairs. It looks very much like the minimum size. It will be very tight with your door to the parents' area. The dining area is too dark for me.
Furniture in the living room seems very small.

Parents' dressing room too narrow.
Access to the parents' area through the bedroom is more than impractical.
Location next to the common room does not ensure restful sleep.
Why not classic sleeping upstairs?

3 bathrooms cost and need to be maintained.

The furniture has a realistic size. These are exactly the pieces of furniture we currently have and will take with us.
The dining table is drawn at 2.30m x 1.30m with chairs. Is that supposed to be too small a table?
Why is the dining room too dark? The entire southwest front is glazed.

Where would you place the wardrobe instead?

The staircase measures 2.10 x 2.80. Too small?

Sleeping upstairs is not an option for us. I already described that in the EP...

1.85m width in the dressing room with an open closet system (46cm depth) is too small?

The existing ground floor has visual charm, I like the deviation from the mass, but I also see the parents' area as a crutch. Maybe a better solution can be created, I would always access it from the dressing room.

Do you have a concrete idea about this? Aside from my suggestion in #13...

Thanks and best regards

1.85m width in the dressing room with an open wardrobe system (46cm depth) is too small?

Wardrobes are 60/65 deep... they don't stand flush against the wall.
With a wall system there are 50cm boards plus rods. And you want to walk between them and have an overview of the stuff. Not stand in a narrow archive corridor.
From close up you can’t see anything.
Often it helps to build a Sims house. They already show you where it gets tight
By the way, this design reminds me a bit of "then I'll just add a room here and here and here — rectangles are overrated anyway and I'll just ignore what's up there on the upper floor" oops:

:

Why no measurements? Both floors are precisely dimensioned in the EP.

Whether a roof terrace is placed on the two cubes or, for cost reasons, a hipped roof, has no influence on the actual floor plan on the upper floor, right?
As mentioned, the wish is for full floor height on the upper floor, then the staircase also works. But since we are not allowed to build two full floors, the upper floor MUST definitely be set back and smaller than the ground floor.

Why don’t you see a day's work? What do you mean by that, can you explain it in more detail?

I was just about to write dressing room as well.

Distance from couch to TV very large.

Maneuvering into the garage would be too stressful for me. Where will the entrance platform go?