Bungalow floor plan 160-170 sqm with basement

It's not about costs, and nobody wants to take your bungalow away from you - both are your choice.

Still, the fact is that you inevitably seal a lot of ground area, thereby reducing your plot size (and 660 sqm isn't that big), and you end up with the typical bungalow problems of a lot of traffic area and little light inside. The basement doesn't improve that... on the contrary: if it doesn't work properly on the ground floor, how is a light well or light court supposed to illuminate the basement interior? That will be a cave!

How about a Bungalow 2.0: a more elongated building with a steeper gable roof, and sauna, relaxation room (library), etc, in the attic? Possibly with an open space to the living area. If you want an L-shape, complemented by a glazed flat-roof cuboid extending into the garden? This one on top as a terrace with a view and exit from the sauna?
So only "just" 120-140 sqm downstairs, and another 40-50 sqm of luxury from the parents' bedroom and wellness upstairs? And thus significantly more of the beautiful plot with the beautiful view?

Especially in the self-planning phase, always draw all rooms with the existing or desired furniture to scale. This way you can best see where it personally gets tight for you.
Does the bookshelf fit, the shoe cabinet, the dream sofa?
In many floor plans, doll furniture is drawn in and the dining area fits in every RV.

Regarding your floor plan
Bedroom: Draw in a wardrobe in the size you want. And not, well then the suits just go to the basement
Guest WC in the private area
Family bathroom extremely large
Children's rooms are not at all in the private area. You always have to go through the large hallway. For that, the orientation of the bedroom would be better. K2 is a bit dark
Living area is large but will not feel generous and bright.
Hallway wardrobe directly at the door. Will almost always look untidy.
Hallway to basement, bathroom quite narrow and dark
Stairs to the basement will not be easily accessible.

Thank God not – compared to this example, one can almost speak of a "clear" design here; the Weiss Vita is no longer a corner bungalow, but rather a twisted bungalow. Besides, I think that in your mid-thirties and with such young children, never ever think about the post-children time or even "old age." Nobody guarantees anyway that ailments will start specifically with arthritis – so seeking salvation in avoiding stairs is rather a questionable wisdom. By the way, you won’t be fit at ninety sitting in an armchair ;-) In any case – not only the specific floor plan, but also the bungalow concept! – don’t fall in love with it too much and first give the architect a chance. For the extra cost of the hip roof corner bungalow, there will be a car by the time of the high school graduation.

I like bungalows and can very well understand the argument. With a basement, I don't have the same feeling of having to manage it as with an upper floor, which creates peace.
The design gives me the impression that it was planned from an external shape inward rather than from an internal need outward.
Where do guests go to the toilet? Almost into the most private area and almost across the whole house. I find that poorly solved.
How do the children get to the bathroom and back? Always through the area where "strangers" are to be expected. The little one doesn't mind, teenagers might find that very unpleasant - as might one or another guest...
How do groceries get into the kitchen? Always past the dining area on a long route. It is more complicated for daily walking distances and ultimately also more to clean. I find that impractical.
It will be tight in the bedroom if clothing in average selection is also to be stored there.
I find the large entrance area successful for a wardrobe and as a possible visual highlight.

If you want to stick to the angled bungalow, try the following shifts: entrance not centered, living room arranged longitudinally instead of transversely to the garden, stairs, WC and entrance hallway in close proximity, private rooms with private access.

As nice as the separation of your own bedroom from the children's rooms is from a certain age of the children - this feature really messes up the structure on your floor plan. Peace and the feeling of seclusion can also be created in adjacent rooms with some architectural additional effort.

Yes, I just have a bit of a fear that the architect will plan according to his own ideas and concepts.

But our wishes come first..

I want to give the architect something so that he at least gets an idea of what we imagine.. but for that I have to start new now......:)