Somehow, the tone in this forum has been getting rougher and more grumpy lately. Just because someone has a plan that someone else can’t really imagine anything sensible about doesn’t mean the plan has to be bad. If you overwhelm a potential builder with accusations, you shouldn’t be surprised if they are put off and dare not frequent this forum in the future.
I like the basic layout of the ground floor, the kitchen is not tiny at all, and the "Speisekammer" is probably meant more as a pantry cupboard. Personally, I would rather do without it and therefore make the rear kitchen workspace wider and accommodate the pantry cupboard in the form of base and wall cabinets on the wider front. But of course, it’s a matter of taste. Alternatively – if the small room is actually not intended as a pantry but rather as a cleaning cupboard, I would give this area a door to the hallway instead of to the kitchen. The door from the entrance area to the kitchen must be there, the door from the kitchen to the (herb) garden also makes sense. Where a utility room is currently drawn, it should probably be a guest room, then the shower makes sense as well.
If I see the door between the kitchen and living area correctly, it’s a sliding door that can disappear completely into the wall, so depending on the type of guests, you can open or close the area, I think that’s great.
The large living room is also great. You call it _derogatorily_ a ballroom – what exactly is wrong with wanting to have space to celebrate with many guests? I once visited friends in Hennef who also have a huge living room, and yes, music is actually played and dancing happens when there are guests. These same friends also happen to have very large children’s rooms for their two children. I think that’s great if you can afford it. For children, it’s wonderful to have plenty of space to play. And it’s also nice that every bedroom has access to a balcony.
The whole concept gives the impression of a luxurious, stylish villa. So, dear builders, good luck!