No run-of-the-mill floor plan in the green with a view of lakes

As I see it, no interior walls are planned here :)

For this design, it's almost worth having an interior designer to optimize the space.

What I would still pay attention to: 25 guests is quite a lot. Here I would put a greater focus on the upper floor. At the moment, there is only one room here. I might perhaps delimit it better somehow.

The 25 never come all at once, at most there are 2 overnight guests with me in the house. I don't want to open a guesthouse ;-)

I would furnish it.

In the non-neutral drawings, cabinets, tables, bed, and kitchen are present. I didn't want to publish such fixed designs in this forum. Maybe someone still has ideas that I like better. I am quite open to that, and that's why I approached the search for ideas this way.

I would provide the attic with a guest room.

Why is the house only 4 m wide when more is possible according to the building boundary?

Because of the roof overhang?

From where does the house access, meaning utility connections? From the east, site plan on the right? Then I find the staircase unfortunately positioned.

What does living kitchen mean to you? Typical L-sofa omitted and e.g. only a kitchen (East Frisian) sofa with a large table?

The shower upstairs is also rather unfavorably placed ... water splashes against the sloping ceiling.

I would also find your furnished versions interesting or even very useful because then one can better see what is important to you. And not just gather ideas blindly.