we have now finally decided on this floor plan.
Have you now made a final decision, or can something still be changed? If something can be changed, I would definitely do it.
This is a typical FriesenGiebel catalog floor plan, right?
I definitely agree with my predecessors, the furniture is way too small, this doesn’t work at all. For example, the sofas in the living room are ridiculous in terms of dimensions. I don't find the whole layout particularly good. It starts at the entrance. You open the door and squeeze past the stairs just to be able to close the front door again. The stair situation upstairs is even worse. The available space in the hallway is halved by the unfortunate (central) position of the stairs. What do you want to do with the dead space on the lower stair side on the upper floor?
As Italiano already said, the wall between the kitchen and the living room is actually unnecessary. It would be better to have a "counter" that also provides cupboard space for the kitchen, because the existing storage space is quite limited.
I don’t find the utility room too big. But it also very much depends on what kind of heating you’ll have, for example. If gas heating, where is the boiler, etc.? In my experience, the attic is not the best place for it (noise and pump problems).
The arrangement in the bathroom is not my taste at all, but that’s a matter of personal preference. However, one should ask how often do I take a bath, and how often do I shower? So how do I arrange it more conveniently... how often do I use the washbasin(s) (usually very often), why are both washbasins crammed together, and where do I find a towel when I’m standing at the washbasin?
Oh yes, where is actually north (left?) and what does the rest of the plot or the surroundings look like? What has to be considered? Slope property? Where is the street? Trees, light, carport, annoying neighbors :) etc.?