Overall, once again, in my opinion, an overly greedy spatial program for the area. With your tinkering, you quickly lose the sense of comfortable room sizes and piece together a bunch of tiny Liliputian rooms where the furniture can just barely fit. Some rooms can no longer be used sensibly, such as the pantry—which is actually quite important. This way, you don’t get a dream house, but at best a stingy apartment with hamster corridors.
If I were you, I would consider cutting this extra room on the ground floor. You have enough bedrooms upstairs, and the children's rooms are big enough for playing. When guests come, the two can just sleep together in one room. Otherwise, you play together in the living room—done.
Alternatively, here is a suggestion with 11.6 x 8.6 meters with normal wall thicknesses. So, a minimally larger ground area. But I hardly see any potential for savings unless another room downstairs is removed. On the contrary, part of the wardrobe already had to move into the guest room.
(the top of the plan is south)
The upper floor is more flexible. Here are two suggestions—there are various possibilities:
