So, unfortunately I have to complain as well, because I find the floor plan really unsuccessful. I don't know the orientation, but I think the garden will be facing south or west. This means the utility room and the guest room (for 4-6 guests/year) as well as the wasteful hallway on the ground and basement floors have gotten the best and brightest spots in the house. And the bedroom, which is used for closing your eyes. You two work in 11 sqm with a tiny window. There's bad air—literally. Hallways also need to be heated and cleaned, so size is not only an advantage. To me, they are way too big, especially on the ground floor... and for that, the kitchen and living area are too small. The pantry is too far from the kitchen.
I would combine the guest room, guest bathroom, and fitness room, use the bright hallway for fitness (plus outdoor fitness area), and move the office upstairs. Fitness could then, if necessary, also become an office. The guest room could get a slope, depending on how important that is for the 4-6 people).
It could then look like this (the staircase is relocated to the other side of the hallway).