May I? I would have it redesigned quite significantly, so I’ll just write something rather general, no details.
The height of all window openings is about 1/3 of the door height, aligned at the top with the doors? That makes, let’s say, 75cm, from which the frames have to be deducted. They end at about 225cm above the floor level, so they start at 150cm. The 9-year-old will still have to grow a bit before he/she can look out of the window. Besides, you write that the rear facade was designed by you. That one is much lighter, so you should ask yourselves if you really want the other sides to be so closed off.
The upper floor facade facing the street with the almost symmetrical, mostly non-opening and low corner windows gives a bit of the impression of a ship’s bridge. I would lower such corner windows and maybe equip them with a window seat bench.
In my opinion, the parent suite is well done.
I find the pantry in that location inconvenient, too far away from the kitchen. You have repurposed it in the plan for the washing machine? You’re of course right, access to the washing machine only via the outside stairs is a crazy idea. Shouldn’t the access to the new laundry room rather be from the hallway? Need to iron something or hang it up to dry overnight in winter? Then it seems way too small at all. If the children’s palace rooms can be smaller, maybe move it upstairs? If the whole thing is being completely redesigned, the area could become the stairwell? Then it could also extend down to the basement. As a requirement, I wouldn’t want to omit an internal access to the basement.
However, I would always want to have a pantry, ideally next to the kitchen and with a short walking distance from the door through which you carry groceries. Especially if basement access is only from outside. Beer crates and sacks of potatoes are simply unsightly (and heavy).
I would be skeptical whether the roof terrace (access only through the children’s room) would be used enough to justify the costs.
The trapped rooms on the upper floor (i.e. only accessible through other rooms) save space in the hallway, but make the whole thing quite inflexible if the rooms are to be repurposed later.