Bathroom planning 3.50 m x 2.86 m

: Which draft are you referring to? Partition walls are already shown in the last two plans I posted.

Quickly as an idea:

Or did I overlook something that speaks against it?

: Thanks for this new version! My opinion on it: The bottom left corner seems to be wasted space. Between the washbasin and the bathtub, it seems very tight.

... I don't understand your argument. In your initial plan, you had a washbasin and bathtub just like Jochen:



Only that Jochen has now placed the toilet at the bottom right so that there is a properly long wall for the washbasin and the shower can be entered generously without anything splashing out.
There would still be space for a towel warmer or something like that.

The space between the washbasin and the bathtub is about 98 cm. I just measured it at our place: 98 cm O_o I don't find that narrow at all. Plenty of space for two or three people to manage in the bathroom. Alternatively, you can make the shower a bit narrower. With 90 x 200 cm, it would still be a huge shower for the whole family (:

The location of the washing area is here but in front of the door. I don't find that appealing either.