Oh, one more thing I forgot to mention. The 3.4m for the kitchen unit with the island is fixed. We already have the kitchen and will be taking it with us.
In our current apartment, we have a kitchen/dining/living area that is 3.4x11m. However, the entrance is directly in the kitchen. We are already used to the fact that you have to plan a bit, especially regarding the dishwasher, and not run it exactly when you want to watch a quiet movie.
In principle, you would probably still tend to choose the side entrance despite the limitations.
My problem with the planning is that we would actually like to have the entrance on the short side; if I subtract the kitchen + stairs from the remaining 7.2m inside, there is about 2m left for the hallway + room... (I hope you can follow my train of thought)
I would just rather not put the utility room on the sunny side so that I can arrange the living/dining area in an L shape...