Semi-detached house on sloping land by the forest

To your semi-detached house

A garden is part of the living space, especially with children. I know it differently, and it was terrible. I am so glad that it is different now and I feel relieved.

I don’t like your back and forth moving either. Especially since on no level do you have two equivalent children’s rooms.

Both basement floors seem to me as if you didn’t really know what to do with them.

The ground floor access to the kitchen through the storage room is really unfavorably designed.

I would locate the terraces barrier-free to the garden and close to the kitchen. For me, a kitchen without garden access would be of little value!

Would you mirror the ground plan of the left semi-detached house on the ground floor? Do you have suggestions to create a shorter path with the groceries to the storage room?

Mirror: no. Arrange differently. If you want care that also requires living space, then using the basement is okay. If the granny flat only exists because of too much space and basement construction, then I would reconsider 3 levels. In the neighborhood, there is a multi-generational house with similar birth years, where the older ones have half of the ground floor, the younger ones the entire upper floor for the children. I would probably do without one level. If definitely with a granny flat, that's okay, but accessibility can also continue into the garden.

Regarding accessibility, those are very good hints! I will read up on the topic more intensively and talk to the architect.

Maybe bring the capable parents on board!? ;) At that age, you still want to be involved in planning!

Especially since accessibility is not the strength of architects.

About the garden: then we would have to move the living rooms to the basement... I need to think about that. Regarding the children's rooms: actually, the idea was that the children would have the entire upper floor to themselves. So "Ankleide" = children's room 2 and "Eltern" = office/playroom. We consciously decided on the concept of a semi-detached house and against a two-family house, as this is simpler / more economical in the event of a sale or rental after the death of my parents (which hopefully will take a very long time). They are, of course, fully involved in the planning.

We consciously decided on the concept of a semi-detached house and against a two-family house,

The mentioned multi-generation house is a truly separated semi-detached house. Semi-detached houses do not have to have the same areas, but can be designed completely individually in size as well as layout without it being "noticeable". I miss that a little here.

Regarding the garden: then we would have to move the living spaces to the basement... I need to reconsider that.

I would indeed reconsider that.
UG is not the same as KG.
In my parents' house, I rather see the kitchen access as you have it. You could also fully use the basement for yourselves and integrate the granny flat with you. The proximity would be given.
Then place the children in the UG next to the granny flat and rather distribute the storage areas on the other floors so that the utility is better distributed.
Due to current circumstances: definitely plan for an infrared cabin option in the older part.