Bathroom planning in existing buildings, improvement suggestions?

Hello everyone,

since the main thread has not yet provided any comments/feedback, I will try with the detailed planning, here for example the bathroom planning. It is an existing house from 1972 that is currently being renovated/restructured. For the planned bathroom, a dormer has already been installed to enlarge the space a bit. Attached is the floor plan with the planned bathroom.

I have attached the current planning once, the most important thing is the floor plan, since the individual objects are unfortunately not available in the online tool exactly as we want them. We had previously swapped the toilet and bathtub, but this made the path to the toilet too narrow.

Are there any comments/improvement suggestions here?

How are the water pipes and, even more importantly, the wastewater pipes laid? They can restrict the planning.

I have marked the existing riser shafts in red (they go from the basement all the way up to the ventilation above the roof.) At the top of the plan (the bathroom floor plan) there is a dead space that can be used for routing pipes. In the house floor plan, this is the dead space at the bottom of the bathroom. Contrary to the plan, the shower head should also be mounted to the left on the wall directly next to the riser shaft (this was not possible with the online planner). Since the floor will be completely rebuilt, water pipes can theoretically also be laid in the floor structure.

How about the following idea:
Shower at the bottom left of the plan as shown, bathtub above. The entrance to the shower would then be on the longer side.
Toilet on the right side of the plan by the window, washbasin below as before.
I don't like the corner bathtub and this way you could avoid it.

How about the following idea:
Bottom left on the plan a shower as drawn, above it a bathtub. The entrance to the shower would then be on the longer side.
On the right side of the plan by the window the toilet, below that the washbasin as before.
I don't like the corner bathtub and this could be avoided this way.

Do you mean like in this old sketch? Note that the sketch is rotated 180° compared to the previous one.
We didn't like this "niche" for the toilet, that's why we swapped it.

By the way, the shower is supposed to be an open, walk-in shower, I should mention. The 1.4m depth is not very generous, but should be sufficient.

No, the bathtub the other way round, directly adjacent to the shower. That’s why the shower entrance is on the long side. The bathroom isn’t very spacious, so an open shower without a door might be too unrealistic. This will be our bathroom, that’s how I would arrange it for you too: