In my opinion, the floor plan just wastes a lot of space. You have 21m² of hallway alone, the wardrobe is neither here nor there and probably only there because the corner next to the stairs was left over.
With reasonable planning, the house could probably be built about 15m² smaller without losing the slightest bit of comfort. Upstairs, for example, I would carve out 8-10m² from the total 43m² children’s rooms for a nice utility room, so you don’t have to carry laundry through the whole house all the time. You can also simply cut out the dressing room given its size and positioning; it brings no added value.
You can also probably eliminate the pantry with the large kitchen. Then place the guest toilet in the pantry’s position, the wardrobe in front of it, and a nice 10m² office next to the stairs upstairs.
Somehow it all feels a bit stuck. I’d recommend firing up Google image searches and letting yourself get inspired a bit more.