Bathroom:
I wouldn’t place the washbasins next to the window sash, rather swap them with the bathtub, but then the deep window wouldn’t fit. (We also have a floor-to-ceiling window in the bathroom and in hindsight, I would have added a railing.
Possibly shift the door slightly to the left or right.
Shower: 90x90?
We have that size, but with a small "seat" about 50cm high and 50cm deep... great for shampoo and such, a seat for the children while showering, comfortable for the wife.
Also, it just feels like you have a lot of space:
