Arrangement in the bathroom of a newly built single-family house

Don't find the layout bad. Move the door towards the oak so that a tall cabinet fits next to the sink.

A few dimensions on the plan would somehow be useful ;)

True! :)

So: Short wall 2 m, the slanted wall 4.2 m and the other walls each 3.6 m

There won’t be many variants here, I’m afraid. The architect’s design is already a very good and solid solution. Here is another variant with a bit more space for a double sink. I have slightly reduced the bedroom and added that space to the bathroom.