Arrangement in the bathroom

You have a 10sqm bathroom. That’s actually okay. You lose almost 2sqm at the bottom of the plan because of the window and the storage areas. In return, you have a shower a little over 75cm wide. That’s too narrow for me. This is the main bathroom, right? And the passage width into the bathroom is also 75cm? Honestly, I don’t like the layout. I personally don’t like a window above the bathtub. But tastes differ on that. If I were to start over, are the windows fixed?

The bathroom in our current apartment is laid out like this. The arrangement is almost like yours except that the shower is where the open space at the bottom is. The toilet is where you have the shower, and where the toilet is now, we have the washing machine & the dryer. If you like this arrangement, a possible utility room could be smaller and you would have more space downstairs for something else.

Otherwise, you have 1/3 of unused space in the bathroom, which would really be a shame. Wasting so much space for just a storage area is not very economical :p

...and if you’re already thinking about the stud wall on the right, then also think about the stud wall on the left, because the bathtub also needs an installation level.

The shower is drawn 90 wide. The windows are not fixed. I'm not a professional and, as I said, I experimented and found this the best, but if other suggestions come, that can change.
At the moment we still have a changing table for our daughter (it will also still be there when we move in), so the space below would also be suitable for that, but of course, a wider shower would also be an idea

Okay, I only looked at it on the smartphone, so the millimeter marks vs. the pen stroke thickness are hard to see.

Don’t you have a changing table in the nursery? Is this supposed to be just an additional one? I would consider whether to plan the bathroom around the changing table, depending on how much longer you’ll need it (from move-in)?

How important is a partition for the toilet to you? At the moment, the half-height wall only prevents people from looking directly at the toilet. If that’s not a priority, try moving the bathtub to where the toilet is. Rotate the toilet 90 degrees and place the plan more to the bottom right.
Then you could use the existing installation wall.
You have to be a bit careful about the height. If wastewater needs to be vented through the roof, the wall can’t be built to the full width only up to shelf height... it must go up to the ceiling somewhere, I think.

Ok, I will ask about the installation of the bathtub (we have an appointment with the structural engineer today anyway). But the wall to the shower also goes up to the ceiling (I'm unsure from your wording whether you assume that or not). Currently, the only changing table is in the bathroom (we find it practical because you have running water immediately at hand if needed), but that is not a priority, it would just be a nice advantage in that variant. If the changing table is no longer needed, I would like to put a cabinet/a shelf there.

For me, the toilet does not necessarily have to be separated by the half-height wall, but my husband finds such partition walls very nice and would like it that way (I also find it nice for decorative purposes)