Why do you find it more sensible for the toilet to be under the slant? Isn’t that structurally difficult?
I find it more harmonious to have the slant at your back. Also, there is no dirty corner next to the tub, and if desired, the toilet paper roll could be mounted more easily and accessibly on the wall.
Shower at a minimum width of 1 meter, after all, that is the shell construction measurement.